JP2017166158A - Construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a construction machine capable of setting a different counter moment with the usage of the same counterweight.SOLUTION: A construction machine includes a work device disposed in front of a front frame, and counterweights 12a and 12b detachably fixed to the rear of the rear frame 7. The construction machine further includes a bolt hole 72a as a first fixing portion for fixing the counterweights 12a and 12b to the rear frame 7 in a first fixing posture attaining a first counter moment, and a bolt hole 72b as a second fixing portion for fixing the counterweights 12a and 12b to the rear frame 7 in a second fixing posture attaining a second counter moment larger than the first counter moment.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a construction machine including a counterweight.

  In construction machines, in order to improve vehicle stability, an auxiliary counterweight for weight increase may be additionally mounted on a standard mounting counterweight (see, for example, Patent Document 1). Alternatively, a weight increasing counterweight may be mounted instead of the standard mounting counterweight.

Japanese Utility Model Publication No. 4-31090

  However, in the apparatus described in Patent Document 1, it is necessary to separately prepare an auxiliary counterweight for increasing the weight, which increases the cost related to the counterweight and causes operations such as component management, drawing creation, and management thereof. There's a problem.

  According to a first aspect of the present invention, there is provided a construction machine comprising: a work device provided at a front portion of a vehicle body frame; and a counterweight detachably fixed to a rear portion of the vehicle body frame. A first fixing portion for fixing to the vehicle main body frame in a first posture and a second posture that causes the counterweight to be a second counter moment greater than the first counter moment. And a second fixing part for fixing.

  According to the present invention, it is possible to set different counter moments using the same counterweight.

FIG. 1 is a side view of the wheel loader. FIG. 2 is a diagram for explaining a fixed form of the counterweight to the rear frame. FIG. 3 is a perspective view showing the appearance of the counterweight. FIG. 4 is a diagram illustrating the configuration of the counterweight fixing portion of the rear frame. FIG. 5 is a diagram for explaining the counter moment. FIG. 6 is a diagram illustrating the departure angle. FIG. 7 is a diagram illustrating a first modification of the counterweight. FIG. 8 is a diagram illustrating a rear frame fixing portion in the first modification. FIG. 9 is a diagram illustrating a first fixed posture and a second fixed posture in the first modification. FIG. 10 is a diagram illustrating a counterweight in the second modification. FIG. 11 is a diagram illustrating a first fixed posture and a second fixed posture in Modification 2.

Embodiment 1
Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a side view showing the appearance of the wheel loader 1. The wheel loader 1 includes a front frame 6 and a rear frame 7 that are rotatably connected to each other by a center pin 100. The front frame 6 is provided with a front tire 10, a front attachment 2, and the like.

  The rear frame 7 is provided with an operator cab 8, an engine compartment 9, a rear tire 11, and the like, and counterweights 12a and 12b are mounted on the left and right of the rear end portion of the rear frame 7, respectively. In FIG. 1, a counterweight 12a is attached to the front side of the figure, and a counterweight 12b is attached to the back side of the figure. The front frame 6 connected to the rear frame 7 via the center pin 100 is refracted right and left with respect to the rear frame 7 by expansion and contraction of a steering cylinder (not shown).

  An engine (not shown) is mounted in the engine chamber 9, and a cooling device 91 including a radiator, a cooling fan, and the like is disposed at the rear end in the engine chamber 9. The cover 92 that covers the cooling device 91 is formed with an intake / exhaust opening 92a through which the intake / exhaust air of the cooling device 91 passes. The counterweights 12a and 12b are shaped so that the upper surface is below the position of the intake / exhaust opening 92a.

  In the front attachment 2, the lift arm 21 rotates in the vertical direction (up and down movement) by the expansion and contraction drive of the lift arm cylinder 20. The bucket 22 provided at the tip of the lift arm 21 is rotated (dumped or clouded) in the vertical direction by the expansion and contraction drive of the bucket cylinder 23. As the link mechanism for driving the bucket 22, a Z link mechanism including a bell crank 24 and a push rod 25 is used.

  The counterweights 12a and 12b serve as counter moments for the load moment applied to the front attachment 2 during excavation work or the load moment applied when a load is loaded on the bucket 22. The present embodiment is characterized by the fixed form of the counterweights 12a and 12b.

  FIG. 2 is a plan view showing the counterweights 12a and 12b fixed to the rear end portion of the rear frame 7. FIG. In FIG. 2, the fixing portion between the counterweight 12b and the rear frame 7 is shown in a broken section. In the present embodiment, the counterweights 12a and 12b can be fixed to the rear frame 7 in two fixed forms (fixed postures) having different counter moments. FIG. 2A shows the first fixed posture, and FIG. 2B shows the second fixed posture.

  In the first fixed posture shown in FIG. 2A, one counterweight 12a is fixed to the left side surface 7a provided on the left side of the vehicle on the rear frame 7, and the other counterweight 12b is positioned on the right side of the vehicle on the rear frame 7. It is fixed to the provided right side surface 7b. Fixing is performed by a bolt 71 and a nut 70. In the second fixed posture shown in FIG. 2B, the fixed arrangement of the counterweights 12a and 12b is reversed left and right with respect to the first fixed posture, and the counterweight 12a is fixed to the right corner of the rear surface 7c of the rear frame 7, The counterweight 12b is fixed to the left corner of the back surface 7c. At the center position of the rear surface 7c of the rear frame 7, a traction device mounting portion 7d is provided. A hole for mounting a connecting pin is formed in the traction device attachment portion 7d.

  FIG. 3 is a perspective view showing the appearance of the counterweight 12a. Two bolt holes 127 for bolting to the rear frame 7 are formed on the surface 125 of the counterweight 12a as shown in FIG. Further, a convex portion 126 that engages with a rectangular hole 73 (see FIGS. 2 and 4) formed in the rear frame 7 is formed on the surface 124 perpendicular to the surface 125. Inclined surfaces 122 and 123 are formed on the lower surface of the counterweight 12a. Further, the upper surface 121 of the counterweight 12a is formed on a surface with less unevenness.

  As shown in FIG. 2, the counterweight 12 a and the counterweight 12 b have a symmetrical shape when viewed from the direction facing the surface 125. Therefore, although illustration is omitted, the shape of the counterweight 12b is the shape of each part (the upper surface 121, the inclined surfaces 122 and 123, the surface 124, the surface 125, the convex portion 126, and the bolt hole 127) except that the shape is symmetrical. Is the same as the counterweight 12a.

  FIG. 4 is a diagram showing the configuration of the counterweight fixing portion in the rear frame 7. In FIG. 4, a part of the left side surface 7a and the right side surface 7b and the back surface 7c are shown. In addition, illustration of the traction apparatus attachment part 7d provided in the back surface 7c of FIG. 4 was abbreviate | omitted. Bolt holes 72a for fixing the counterweights 12a, 12b are formed in the rear end portions of the both side surfaces 7a, 7b, and counterweights 12a, 12b are provided in the left and right end portions on the left and right sides of the rear surface 7c. Bolt holes 72b for fixing are formed. On both side surfaces 7a and 7b and the back surface 7c, rectangular holes 73 with which the convex portions 126 engage are formed in association with the bolt holes 72a and 72b.

  In the case of the first fixed posture shown in FIG. 2A, the counterweight 12a is attached to the left side surface 7a, and the counterweight 12b is attached to the right side surface 7b. When attaching the counterweight 12a to the left side surface 7a, the convex portion 126 is engaged with the rectangular hole 73 formed in the left end portion of the back surface 7c, and the bolt hole 127 is opposed to the bolt hole 72a of the left side surface 7a. Let Then, the counterweight 12 a is fixed to the rear frame 7 by inserting the bolt 71 from the cavity 121 and fastening the nut 70 from the inside of the rear frame 7. Similarly, when the counterweight 12b is attached to the right side surface 7b, the convex portion 126 is engaged with the rectangular hole 73 formed in the right end portion of the back surface 7c, and the bolt hole 127 is engaged with the bolt hole 72a of the right side surface 7b. Make them face each other. Then, the counterweight 12 b is fixed to the rear frame 7 by inserting the bolt 71 from the cavity 121 and fastening the nut 70 from the inside of the rear frame 7.

  On the other hand, in the second fixed posture shown in FIG. 2B, the counterweight 12a is attached to the right end portion of the back surface 7c, and the counterweight 12b is attached to the left end portion of the back surface 7c. When the counterweight 12a is attached to the right end portion of the back surface 7c, the convex portion 126 is engaged with the rectangular hole 73 formed in the right side surface 7b, and the bolt hole 127 is formed in the right end portion of the back surface 7c. It faces the bolt hole 72b. Then, the counterweight 12 a is fixed to the rear frame 7 with the bolt 71 and the nut 70. When attaching the counterweight 12b to the left end portion of the back surface 7c, the convex portion 126 is engaged with the rectangular hole 73 formed in the left side surface 7a, and the bolt hole 127 is formed in the left end portion of the back surface 7c. It faces the bolt hole 72b. Then, the counterweight 12 b is fixed to the rear frame 7 with the bolt 71 and the nut 70.

  FIG. 5 is a diagram for explaining the counter moment in the first and second fixed postures. In FIG. 5, (a) shows the case of the first fixed posture, and (b) shows the case of the second fixed posture. G1 and G2 indicate the gravity center positions of the counterweights 12a and 12b, respectively. The position indicated by symbol G indicates the total center of gravity position of the two counterweights 12a and 12b.

  In the case of the first fixed posture shown in FIG. 5A, the distance from the axle of the front tire 10 to the gravity center position G is L1. When the total weight of the counterweights 12a and 12b is W, the counter moment is represented by the product (L1 × W) thereof. On the other hand, in the second fixed posture shown in FIG. 5B, the distance L2 from the axle of the front tire 10 to the center of gravity G is longer than the distance L1 (L2> L1), and the counter moment (L2 × W) is larger than the counter moment (L1 × W) in the first fixed posture. For example, it is used in the first fixed posture in normal work where the load moment is lower than the rating, and is used in the second fixed posture in order to improve the vehicle body stability during heavy work where the load applied to the front attachment is large.

  Thus, in this embodiment, the counter moment can be changed by changing the fixed posture of the counterweights 12a and 12b. Therefore, it is not necessary to prepare another weight increasing counterweight in addition to the standard mounting counterweight, unlike the conventional construction machine.

  Further, by adopting a structure in which the convex portions 126 of the counterweights 12a and 12b are engaged with the rectangular holes 73 formed in the rear frame 7, it can be used for positioning and holding the counterweight when the bolt is fixed. The workability of the fixing work can be improved.

  In the above-described embodiment, the bolt holes 127 are formed on the surface 125 of the counterweights 12a and 12b and the convex portions 126 are formed on the surface 124. Conversely, the bolt holes 127 are formed on the surface 124 and the surface 125 is formed. The convex portion 126 may be formed on the surface. In this case, in the first fixed posture shown in FIG. 2A, the counterweights 12a and 12b are fixed to the rear frame 7 using the bolt holes 72b on the back surface 7c. On the other hand, in the second fixed posture shown in FIG. 2B, the counterweights 12a and 12b are fixed to the rear frame 7 using bolt holes 72a formed in the side surfaces 7a and 7b.

  FIG. 6 is a diagram illustrating the departure angle. FIG. 6B shows a case where the wheel loader 1 goes up a slope. The counterweights 12a and 12b are mounted in the second fixed posture. The angle α is the slope angle. The wheel loader 1 can move up and down the slope at the predetermined angle α, that is, the departure angle α as shown in FIG. 6A so that the vehicle body behind the rear tire 11 does not interfere with the ground. Is secured. Assuming a surface S that passes through the grounding point P and is inclined with respect to the horizontal plane, the upper limit angle α at which the inclined surface S maintains a non-contact state with the lower part of the vehicle body is the departure angle.

  In the present embodiment, inclined surfaces 122 and 123 are formed on the lower surfaces of the counterweights 12a and 12b in order to ensure the departure angle α. The inclined surface 123 is formed so that the departure angle α is secured when the counterweights 12a and 12b are fixed to the rear frame 7 in the first fixed posture. In the first fixed posture, the inclined surface 123 is inclined upward in the vehicle from the vehicle front end side to the vehicle rear end side of the counterweights 12a and 12b. On the other hand, the inclined surface 122 is formed so as to ensure the departure angle α in the second fixed posture. Also in this case, the inclined surface 122 is inclined upward in the vehicle from the vehicle front end side to the vehicle rear end side of the counterweights 12a and 12b. Thus, the departure angle α is ensured in both the first fixed posture and the second fixed posture.

  As shown in FIG. 1, a cooling device 91 including a radiator, a cooling fan, and the like is disposed at the rear end of the engine chamber 9, and an intake / exhaust air through which the cooling device 91 passes through a cover 92 that covers the cooling device 91. An exhaust opening 92a is formed. The upper end position (the highest position of the upper surface) of the counterweight fixed to the rear frame 7 is the intake / exhaust opening 92a (the lowermost position) in the vehicle height direction in both the first and second fixed postures. The position is lower than the intake / exhaust opening 92a). Therefore, the counterweights 12a and 12b provided at the rear end portion of the rear frame 7 do not hinder intake / exhaust. Of course, when there is no intake / exhaust opening at the position where the counterweight is arranged, there is no need to provide such a restriction on the height dimension of the counterweight.

  Further, as shown in FIG. 2, a traction device attachment portion 7 d may be provided at the center position of the rear frame 7. Considering such a case, the shapes of the counterweights 12a and 12b are formed so as not to hinder the use of the traction device mounting portion 7d as shown in FIG.

(Modification 1)
FIG. 7 is a diagram illustrating a first modification of the counterweight. FIG. 8 is a view showing a fixing portion of the rear frame 7 to which the counterweight of FIG. 7 is fixed. The counterweight 32 shown in FIG. 7 is different from the counterweights 12a and 12b of the first embodiment in the shape of a fixing portion for fixing to the rear frame 7. In addition, in FIG. 8, illustration of the traction apparatus attachment part 7d provided in the back surface 7c was abbreviate | omitted.

  In the counterweight 12a shown in FIG. 3, the two surfaces 124, 125 formed in an L-shape are the side surfaces 7a, 7b (in the second fixed posture) or the rear surface 7c (the first fixed posture) of the rear frame 7. In the case of). On the other hand, in the counterweight 32 shown in FIG. 7, the surface 325 facing the rear frame 7 is constituted by a single plane, and four bolt holes 327 are formed on the surface 325 as fixing portions. The counterweight 32 has a symmetrical shape with respect to the center line L10, and an inclined surface 322 and a pair of inclined surfaces 323 are formed on the lower surface.

  As shown in FIG. 8, four bolt holes 74a are formed in the rear end portions of the left side surface 7a and the right side surface 7b, respectively. In addition, four bolt holes 74b are formed in the left and right end regions of the back surface 7c. In the first fixed posture in the modified example 1, as shown in FIG. 9A, the counterweight 32 is bolted to the left side surface 7a and the right side surface 7b using the bolt holes 74a formed in the side surfaces 7a and 7b. And fix with a nut 70. On the other hand, in the case of the second fixing posture, the counterweights 32 are respectively fixed to the left and right end portions of the back surface 7c using the bolt holes 74b formed in the back surface 7c as shown in FIG. 9B. The counterweight 32 is formed with a hollow portion 321 for inserting the bolt 71.

  The pair of inclined surfaces 323 are inclined surfaces provided to ensure the departure angle α in the first fixed posture. On the other hand, the inclined surface 322 is an inclined surface provided to ensure the departure angle α in the second fixed posture.

(Modification 2)
In the counterweights 12a and 12b of the first embodiment shown in FIG. 3 and the counterweight 32 of the first modification shown in FIG. 7, the rear frame 7 has fixing portions (bolt holes) corresponding to the first and second fixing postures. 72a, 72b or 74a, 74b), and the first fixed posture or the second fixed posture is set depending on which fixing portion the counterweight is fixed to. On the other hand, in Modification 2, two sets of fixing portions are provided on the counterweight side.

  FIG. 10 is a view showing a counterweight 42a in the second modification. In the counterweight 42a, the upper surface 421, the inclined surfaces 422 and 423, the surfaces 424 and 425 have the same configuration as the upper surface 121, the inclined surfaces 122 and 123, and the surfaces 124 and 125 of the counterweight 12a shown in FIG. The following configuration is different from the counterweight 12a. Four bolt holes 427 are formed in each of the surfaces 424 and 425. The counterweight 42a shown in FIG. 10 corresponds to the counterweight 12a described above, and includes a counterweight 42b corresponding to the counterweight 12b, although not shown.

  FIG. 11 is a diagram illustrating a first fixed posture and a second fixed posture when the counterweights 42a and 42b are used. FIG. 11A shows the first fixed posture. The counterweight 42a is fixed to the left side surface 7a of the rear frame 7 using a bolt hole 427a provided on the surface 425 (see FIG. 10). Similarly, the counterweight 42 b is fixed to the right side surface 7 b of the rear frame 7 using a bolt hole 427 a provided on the surface 425. Bolt holes 75 are formed in the left side surface 7a and the right side surface 7b at positions corresponding to the respective bolt holes 427a. Cavities 421a and 421b for inserting bolts 71 are formed in the counterweights 42a and 42b, respectively.

  FIG. 11B shows the second fixed posture. The counterweight 42a is fixed to the right side surface 7b of the rear frame 7 using a bolt hole 427b provided on the surface 424 (see FIG. 10). Similarly, the counterweight 42b is fixed to the left side surface 7a of the rear frame 7 using a bolt hole 427b provided in the surface 424.

  As described above, the wheel loader 1 includes the counterweights 12a and 12b detachably attached to the rear portion of the rear frame 7 (vehicle body frame) as shown in FIG. Then, as shown in FIG. 4, a bolt hole 72a (first fixing portion) for fixing the counterweights 12a, 12b to the rear frame 7 in the first fixing posture at which the first counter moment (L1 × W) is obtained. , Bolt holes 72b (second fixing portions) for fixing the counterweights 12a, 12b in the second fixing posture, which is the second counter moment, which is larger than the first counter moment (L1 × W), Prepare for frame 7.

  As described above, since the set of counterweights 12a and 12b can be changed between different fixed postures, two different types of counter moments are possible using the set of counterweights 12a and 12b. Therefore, unlike the conventional construction machine, it is not necessary to prepare another weight increase counterweight in addition to the standard counterweight (corresponding to the counterweights 12a and 12b in the first fixed posture).

  In the configuration shown in FIGS. 2 and 4, a bolt hole 72 a as a first fixing portion and a bolt hole 72 b as a second fixing portion are provided in the rear frame 7. On the other hand, in the configuration shown in FIGS. 10 and 11, a bolt hole 427a as a first fixing portion and a bolt hole 427b as a second fixing portion are provided in the counterweights 42a and 42b.

  In addition, as shown in FIG. 3, when the bolt holes 127 are formed on the surfaces 125 of the counterweights 12a and 12b and the convex portions 126 are formed on the surfaces 124, the bolt holes 72a as the first fixing portions are formed on the rear frame. 7 is provided on the left and right side surfaces 7 a and 7 b, and the bolt hole 72 b as the second fixing portion is provided on the rear surface 7 c of the rear frame 7. On the other hand, when the bolt hole 127 is formed on the surface 124 and the convex portion 126 is formed on the surface 125, the bolt hole 72b functions as the first fixing portion, and the bolt hole 72a functions as the second fixing portion. To do.

  In addition, the above description is an example to the last, and this invention is not limited to the said embodiment at all unless the characteristic of this invention is impaired. For example, in the above-described embodiment, the counterweight of the wheel loader has been described as an example. However, the present invention can be applied to various construction machines including a counterweight such as a counterweight of a hydraulic excavator.

  DESCRIPTION OF SYMBOLS 1 ... Wheel loader (construction machine), 2 ... Front attachment (work apparatus), 6 ... Front frame (vehicle body frame), 7 ... Rear frame (vehicle body frame), 7a ... Left side surface, 7b ... Right side surface, 7c ... Rear surface (rear surface of vehicle main body frame), 7d: Traction device mounting portion, 12a, 42a: Counter weight (first counter weight), 12b, 42b: Counter weight (second counter weight), 32: Counter weight (first counter) Weight, second counterweight), 122, 322, 422 ... inclined surface (second inclined surface), 123, 323, 423 ... inclined surface (first inclined surface), 72a, 74a, 427a ... bolt holes (first fixed) Part), 72b, 74b, 427b ... bolt hole (second fixing part), 91 ... cooling device, 92 ... cover (vehicle cover), 2a ... intake and exhaust openings, L1 ... counter moment (first counter moment), L2 ... counter moment (second counter moment)

Claims (6)

In a construction machine comprising a working device provided at a front portion of a vehicle body frame and a counterweight detachably fixed to a rear portion of the vehicle body frame,
A first fixing portion for fixing the counterweight to the vehicle body frame in a first posture that becomes a first counter moment; and a second counter moment that has a second counter moment larger than the first counter moment. And a second fixing portion for fixing the vehicle body frame to the vehicle body frame. The construction machine according to claim 1,
The first fixing portion is provided on a side surface of the vehicle body frame,
The second fixing portion is provided on a rear surface of the vehicle body frame;
The construction machine characterized in that the counterweight is selectively fixed to one of the first fixing part and the second fixing part. The construction machine according to claim 2,
The first fixing portion and the second fixing portion are provided on the left and right side surfaces and the left and right sides of the vehicle body frame,
The counterweight is fixed to a first fixing portion provided on a left side surface of the vehicle body frame in the first posture, and on a right side surface of the vehicle body frame in the first posture. A second counterweight fixed to the provided first fixing portion,
In the second posture, the first counterweight is fixed to a second fixing portion provided on the right side surface of the vehicle body frame, and the second counterweight is provided on the left side surface of the vehicle body frame. A construction machine that is fixed to the second fixing portion. The construction machine according to claim 3,
On the lower surface of the counterweight,
In the first posture, a first inclined surface that inclines in the vehicle upward direction from near the center of the counterweight to the vehicle rear end side of the counterweight;
A construction machine characterized in that, in the second posture, a second inclined surface that is inclined in the vehicle upward direction toward the vehicle rear end side of the counterweight is formed. The construction machine according to claim 3,
A cooling device is provided inside the vehicle cover mounted on the rear portion of the vehicle body frame,
An intake / exhaust opening through which the intake / exhaust air of the cooling device passes is formed in the vehicle cover,
The construction machine is characterized in that the counterweight is disposed at a position lower than the intake / exhaust opening in the vehicle height direction in any of the first and second postures. The construction machine according to claim 3,
The construction machine according to claim 1, wherein the counterweight is arranged at a position not interfering with a vehicle body traction device attached to a rear surface of the vehicle body frame.

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