JP2013155494A - Work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a restriction structure that restrains a cab in a case of abnormality.SOLUTION: There is provided a work machine provided with a machine body 3 on a lower traveling body 2. The machine body 3 includes a cab 5 installed on a base frame 7 so that a panel member 21 L on the side of a door 23 constitutes a side face of the machine body 3, and a restriction structure 30 which stops the cab 5 from tilting abnormally. The base frame 7 has a side deck 13 fitted to a bottom plate 11 and supporting the cab 5 through a vibration insulation mount. The restriction structure 30 has an engagement pin 32 and an engagement member 34 having an engagement hole 41 formed having an inner diameter larger than an outer diameter of the engagement pin 32. The engagement pin 32 is inserted into the engagement hole 41, and the engagement member 34 is soldered and fixed to the bottom plate 11 so that the center C of the engagement hole 41 is aligned with an axis A of the engagement pin 32.

Description

  The present invention relates to a work machine such as a hydraulic excavator or a crane, and more particularly to a work machine provided with a restraint structure that prevents a cab from being largely overturned when an abnormal impact is applied to the cab due to a fall or the like.

  A basic configuration of this type of restraint structure is disclosed in, for example, a hydraulic excavator disclosed in Patent Document 1.

  Specifically, in the hydraulic excavator, a raised portion having an inverted U-shaped cross section having front and rear walls and an upper wall is projected on the base frame of the upper swing body, and the upper wall of the raised portion is A mounting mount having an anti-vibration mechanism is fixed in a state of penetrating the upper wall. The cab is supported by the base frame via the mounting mount, and a pair of left and right restraining means are provided at the rear of the cab.

  Each restraining means includes a shaft member and a plate. The shaft member is fixed to a beam member disposed so as to extend in the left-right direction on the lower rear side of the cab with the shaft main body protruding rearward.

  An insertion hole larger than the shaft main body is formed in the upper portion of the plate, and the shaft main body is inserted so as not to contact the insertion hole. A retaining ring is attached to the protruding end of the shaft main body inserted through the insertion hole. And the lower end part of the plate is being fixed to the rear wall of the protruding part mentioned above with the volt | bolt.

  If the excavator having such a structure is provided in the hydraulic excavator, even if the cab is lifted abnormally, the shaft member is in contact with the plate, so that the abnormal rise of the cab can be restricted and the safety can be improved.

JP 2009-133119 A

  When the restraint structure performs its function, a large force is applied to the shaft member and the plate. Therefore, when a plate is attached to the raised portion as in the restraining means of Patent Document 1, the force is transmitted to the raised portion through the plate.

  At the same time, the force applied to the shaft member is also transmitted to the raised portion through the mounting mount, so that the raised portion must receive all the force applied to the restraining means. Therefore, it is necessary to strengthen the strength and rigidity of the raised portion and its peripheral portion so that it can withstand it.

  For this purpose, it is necessary to increase the plate thickness of the raised portion or to add a member to the raised portion to reinforce, and there are problems such as an increase in manufacturing cost and a complicated structure.

  In particular, in the rear small turning type model, unlike the standard model, the rear portion of the base frame is narrowed to reduce the turning radius, and the space behind the cab is limited. For this reason, it is difficult to provide the restraint structure of the above-described structure in the conventional rear small turning type model, and this is dealt with by directly strengthening the mounting mount or the like instead of providing the restraint structure. As a result, the member cost is high, and there has been a demand for cost reduction.

  Accordingly, an object of the present invention is to provide a work machine equipped with a restraint structure that is suitable for a small rear turning type model, can effectively receive an abnormal force applied to the cab, and can realize cost reduction. There is.

  The work machine of the present invention is a work machine in which a machine body is provided on a lower traveling body. The machine body has a cab installed on the base frame and an abnormal inclination of the cab so that the base frame and the panel member on the door side constitute either the left or right side of the machine body. And a restraining structure for blocking.

  The base frame includes a bottom plate supported by the lower traveling body, and a side deck attached to the bottom plate so as to project and supporting the cab via a vibration-proof mount. The restraint structure includes an engagement pin that protrudes rearward from the lower rear side of the cab, and an engagement member in which an engagement hole having an inner diameter larger than the outer diameter of the engagement pin is formed. .

  The engagement pin is inserted into the engagement hole, and the engagement member is fixed to the bottom plate by welding so that the center of the engagement hole coincides with the axis of the engagement pin.

  According to this work machine, since the engaging member is directly fixed to the bottom plate by welding, the load transmitted by the contact of the engaging pin can be directly transmitted to the bottom plate. Therefore, although it is a simple structure, the abnormal force added to a cab can be received effectively and cost can also be reduced.

  In a specific example, the cab includes a frame member that extends in the vertical direction along the rear edge of the panel member. The engagement pin is attached to the frame member. The engaging member is formed of a plate member having the engaging hole formed in the front surface and left and right ends extending in parallel in the vertical direction. The center of the engagement hole is formed to be biased toward the side surface of the machine body.

  In this case, since the engagement pin is attached to the frame member that extends in the vertical direction along the rear edge of the cab panel member that constitutes the side surface of the machine body, for example, the work machine falls and the cab When an impact is applied to, the impact can be effectively transmitted to the engagement pin.

  In this case, it is necessary to provide the engagement hole in the vicinity of the side edge of the bottom plate corresponding to the engagement pin, but this can be easily realized by forming the center of the engagement hole biased. The load transmitted from the mating pin can be effectively transmitted to the bottom plate.

  In this case, a reinforcing plate fixed to the side end and the bottom plate by welding is provided on each of the left and right side ends of the engaging member, and the reinforcing plate positioned on the side surface of the machine body is It is preferable to extend upward from the upper end of the engagement hole.

  By doing so, a sufficient amount of welding can be secured, and the cross-sectional area in the direction in which the load is applied can be increased, so that the strength and rigidity of the engaging member can be enhanced. Since the reinforcing plate closer to the engagement hole extends above the upper end of the engagement hole, the engagement member is strengthened in a well-balanced manner even if the engagement hole is formed biased on the engagement member. Thus, the load applied to the engaging member can be efficiently transmitted to the bottom plate.

  For example, when an engine room is installed in the vicinity of the rear part of the cab and the engine room has a partition panel for partitioning the engine room at the rear of the cab, A work opening that allows the engagement pin to be extracted from the hole is formed, and a cover member that closes the work opening may be detachably provided on the partition panel.

  If it does so, since an engagement pin can be extracted from an engagement hole through a work opening from an engine room, even if a restraint structure is provided, a cab can be easily removed from a base frame. Therefore, the present invention can also be applied to a small rear turning type model with a limited space.

  Since the work opening is closed by a detachable cover member, the function of the partition plate can be secured even if the work opening is formed in the partition plate.

  According to the work machine of the present invention, an abnormal force applied to the cab by the restraint structure can be effectively received. Since the structure of the restraint structure is also simplified, the cost can be reduced.

It is a schematic perspective view which shows the working machine of this embodiment. It is a schematic perspective view which shows the principal part structure of a base frame and a cab. It is a schematic plan view which shows the structure of a part of base frame. It is a schematic perspective view which shows a restraint structure. It is the schematic sectional drawing seen from the XX line in FIG. It is the schematic which expands and shows the principal part of FIG. It is the schematic seen from the arrow Y direction in FIG. It is the schematic perspective view which looked at the action part from the engine room. It is the schematic which shows the modification of a restraint structure. 4A is a diagram corresponding to FIG. 4, and FIG. 6B is a diagram corresponding to FIG. It is the schematic which shows the modification of a restraint structure. 4A is a diagram corresponding to FIG. 4, and FIG. 6B is a diagram corresponding to FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the following description is merely illustrative in nature and does not limit the present invention, its application, or its use. In each figure, the up / down and front / rear / left / right directions are indicated by arrows. Unless stated otherwise, the vertical direction will be described according to the directions indicated by these arrows.

(Overall configuration of work machine)
FIG. 1 shows a hydraulic excavator 1 to which the present invention is applied. The hydraulic excavator 1 includes a crawler-type lower traveling body 2 and a machine main body 3 that is rotatably installed on the lower traveling body 2. The machine body 3 includes an attachment 4, a cab 5, an engine room 6, a base frame 7, and the like. Incidentally, the excavator 1 of the present embodiment is a small rear turning type. The machine body 3 is configured to be relatively small so that the turning radius is small, and the outline of the rear part of the machine body 3 is formed in an arc shape when viewed from above.

  The attachment 4 is installed in the front part of the machine main body 3, and is comprised by the boom 4a, the arm 4b, the bucket 4c, etc. Each of the booms 4a and the like operates in conjunction with the expansion and contraction of the hydraulic cylinder 4d that is hydraulically controlled, and performs operations such as excavation. The operations of the boom 4a and the like are performed in the cab 5.

  The cab 5 is a rectangular box-shaped cab, and is installed on the left front side of the machine body 3 adjacent to the attachment 4. On the left side surface of the cab 5 constituting the left side surface of the machine body 3, a door 23 is provided for an operator to enter and exit the cab 5. Details of the structure of the cab 5 will be described later.

  The engine room 6 is installed in the rear part of the machine body 3 in a state of being close to the rear part of the cab 5. Inside the engine room 6, although not shown, an engine, hydraulic equipment, and the like are housed in a dense state. In the hydraulic excavator 1, the rear portion of the engine room 6 is covered with a counterweight 9.

  Openings are formed in the left and right sides of the counterweight 9 so that maintenance can be performed. Door covers 9a and 9b that can swing and open are attached to these openings.

  As shown in detail in FIGS. 2 and 3, the base frame 7 is installed in the lower part of the machine body 3, and the cab 5, the engine room 6, and the like are arranged on the base frame 7. The base frame 7 includes a bottom plate 11, a pair of vertical plates 12, 12, a side deck 13, and the like. Note that the base frame 7 in these drawings is simplified for convenience.

  The bottom plate 11 is a thick metal plate that expands in the horizontal direction, and a central portion of the bottom plate 11 is supported by the lower traveling body 2 so as to be rotatable. On the bottom plate 11, a pair of vertical plates 12, 12 are erected. Each vertical plate 12 is made of a thick metal plate having a substantially triangular appearance with a top portion unevenly distributed on the front side when viewed from the left-right direction, and the left and right intermediate portions of the bottom plate 11 are opposed to each other in the left-right direction. While extending in the front-rear direction.

  A cylinder support portion 12a that rotatably supports the hydraulic cylinder 4d is provided at the front end portion of each vertical plate 12. And the boom support part 12b which supports the boom 4a rotatably is provided in the top part of each vertical board 12 following the cylinder support part 12a.

  A fastening seat for attaching the counterweight 9 is provided at the rear part of the bottom plate 11 constituting the floor surface of the engine room 6. Specifically, end fastening seats 15a are provided at both left and right ends of the rear edge of the bottom plate 11, and a central fastening seat 15b is provided between the end fastening seats 15a and 15a. The fastening seats 15 a and 15 b are fixed to the upper surface of the bottom plate 11 by welding and integrated with the bottom plate 11. Accordingly, the fastening seats 15a and 15b can be viewed with the bottom plate 11.

  As shown in FIG. 3, the frame-shaped side deck 13 is attached so as to protrude from the left front portion of the bottom plate 11 corresponding to the arrangement of the cab 5. The side deck 13 is provided with four mounts 16 corresponding to the arrangement of the four corners of the cab 5.

  A round hole is opened on the upper surface of each mount base 16. An anti-vibration mount M having an anti-vibration function is installed in the round hole (the anti-vibration mount M is shown only in FIG. 5). The cab 5 is supported by the base frame 7 via the vibration isolation mount M. Therefore, the vibration of the base frame 7 generated when the hydraulic excavator 1 is operated is reduced by the anti-vibration mount M, and the cab 5 is not greatly shaken.

  As shown in FIG. 2, the cab 5 includes a panel member 21 that covers the periphery, a rectangular box-shaped frame 22 that supports the panel member 21, and the like.

  Specifically, the front, rear, left and right four surfaces and the upper surface of the cab 5 are covered with a panel member 21 made of a steel plate or the like. A transparent window is provided on the upper part of the panel member 21 covering the front, rear, left and right four surfaces. In addition, the above-described swing opening / closing door 23 is provided on the front side portion of the left panel member 21 (also referred to as the left panel member 21L).

  The frame body 22 is configured by connecting a plurality of frame members to each other. Each frame member is formed of a hollow steel pipe or the like having a rectangular cross section, and is provided so as to extend in the vertical direction, the horizontal direction, and the front-back direction along the edge of the cab 5.

  For example, a front column frame 22a and a rear column frame 22b that extend in the vertical direction along the front edge and the rear edge are provided around the left panel member 21L, and extend in the front-rear direction along the lower edge and the upper edge. Beam frames 22c and 22c are provided.

  The cab 5 is structurally strengthened by the panel member 21 and the frame body 22, and an abnormal situation such as a fall of the hydraulic excavator 1 occurs and an abnormal shock is applied to the cab 5. It is designed not to collapse easily. Further, a restraining structure 30 for preventing an abnormal inclination of the cab 5 is provided on the rear side of the cab 5 so that the cab 5 does not lift from the base frame 7 when such an abnormal situation occurs. Yes.

  In the hydraulic excavator 1, one restraining structure 30 is provided in a portion (also referred to as an action site S) where the left corner on the lower rear side of the cab 5 is located. In the case of this excavator 1, the excavator 1 falls and a large external force acts on the cab 5 mainly when the excavator 1 falls to the left side. In this case, the cab 5 usually moves to the upper right. Tilt toward. That is, the left side of the cab 5 is easily lifted. Therefore, if it is the action part S, even if the restraint structure 30 is one, the abnormal inclination of the cab 5 can be prevented effectively.

(Specific configuration of restraint structure)
4 and 5 show the constraining structure 30 in an enlarged manner. The restraint structure 30 includes an engagement pin 32, an engagement plate 34 (an example of an engagement member), a reinforcing plate 36, a retaining member 38, and the like.

  The engagement pin 32 is made of a round bar-like member, and is detachably fixed to the lower end portion of the rear support frame 22b. Specifically, the front end portion of the engagement pin 32 is fastened and fixed to a boss portion 22d provided on the front wall of the rear column frame 22b. The engaging pin 32 is provided such that its axis A extends substantially horizontally in the front-rear direction. A portion on the rear side of the front end portion of the engagement pin 32 penetrates the rear wall of the rear support frame 22b and protrudes rearward from the cab 5.

  As shown in FIGS. 6 and 7, the engagement plate 34 is made of a metal plate member whose left and right side edges 34 a and 34 b extend in parallel in the vertical direction and whose front and rear surfaces are substantially rectangular. The engagement plate 34 is fixed to the bottom plate 11 by welding while straddling a part of the left end fastening seat 15a (also referred to as the left end fastening seat 15a).

  Specifically, the left end fastening seat 15 a is provided so as to extend rearward along the edge of the bottom plate 11 in the action site S. A counterweight 9 is attached to the rear portion of the left end fastening seat 15a. In the left front portion of the left end fastening seat 15a, there is provided a gap portion 40 where the bottom plate 11 is exposed when the left end fastening seat 15a is recessed rightward.

  The lower right portion of the engagement plate 34 is recessed in a rectangular shape, and the left front portion of the left end fastening seat 15a is fitted therein, and both portions are welded. The lower left portion of the engagement plate 34 enters the gap 40 and is welded to the bottom plate 11.

  An engagement hole 41 penetrating in the front-rear direction is formed in the upper part of the front surface of the engagement plate 34. The engagement hole 41 is an oval hole that is slightly longer in the vertical direction, and has an inner diameter larger than the outer diameter of the engagement pin 32. When the cab 5 is installed at a predetermined position of the base frame 7, the engagement pin 32 is inserted into the engagement hole 41 so that the axis A of the engagement pin 32 and the center C of the engagement hole 41 coincide with each other. The engagement plate 34 is disposed.

  The relationship between the outer diameter of the engagement pin 32 and the inner diameter of the engagement hole 41 is designed so that the engagement pin 32 does not come into contact with the engagement plate 34 even if the cab 5 swings in the normal operation state of the excavator 1. ing. When an impact is applied to the cab 5 due to the fall of the excavator 1 and the cab 5 tilts abnormally, the engagement pin 32 contacts the engagement plate 34. As a result, the cab 5 is directly received by the bottom plate 11 and further tilting is prevented.

  The center C of the engagement hole 41 is formed to be biased toward the left side surface of the machine body 3.

  Specifically, as shown in FIG. 7, when viewed from the front-rear direction, the distance L1 from the left end 34a of the engagement plate 34 to the center of the engagement hole 41 is from the right end 34b of the engagement plate 34. The engagement hole 41 is formed at a position smaller than the distance L2 to the center of the hole 41. By doing so, the restraint structure 30 can be provided in the action part S, and the abnormal inclination of the cab 5 can be effectively prevented.

  That is, the impact applied to the cab 5 can be efficiently transmitted to the engagement pin 32 by fixing the engagement pin 32 to the lower end portion of the rear support frame 22b. In that case, the engagement hole 41 needs to be provided in the vicinity of the left side edge of the bottom plate 11, but it can be easily achieved by forming the center C of the engagement hole 41 so as to be biased toward the left side surface of the machine body 3. The load transmitted from the engagement pin 32 can be effectively transmitted to the bottom plate 11.

  Further, in order to reinforce the engagement plate 34, two reinforcing plates 36 are provided.

  These reinforcing plates 36 are made of a band-shaped metal plate material, and are provided on the left and right side ends 34a and 34b of the engagement plate 34 so that the cross sections thereof are I-shaped or T-shaped. It is fixed to the bottom plate 11 by welding. A lower end of a reinforcing plate 36 (also referred to as a first reinforcing plate 36 a) located on the left side of the machine body 3 is fixed to the upper surface of the bottom plate 11 exposed in the gap 40. The lower end of the other reinforcing plate 36 (also referred to as the second reinforcing plate 36b) is fixed to the upper surface of the left end fastening seat 15a.

  By doing so, a sufficient amount of welding can be secured, and the cross-sectional area in the direction in which the load is applied can be increased, so that the strength and rigidity of the engagement plate 34 can be enhanced.

  The first reinforcing plate 36 a is longer than the second reinforcing plate 36 b and extends upward from the upper end of the engagement hole 41. By doing so, even if the engagement hole 41 is formed in the engagement plate 34 in a biased manner, the engagement plate 34 can be strengthened in a balanced manner, and the load applied to the engagement plate 34 can be efficiently transmitted to the bottom plate 11. Can do. Since the second reinforcing plate 36b is short, the member cost can be reduced.

  The rear end portion of the engagement pin 32 protrudes rearward from the engagement hole 41. A ring-shaped retaining member 38 having a ring shape is fixed to the protruding portion with a nut. The retaining member 38 has an outer diameter larger than that of the engagement hole 41, and restricts the engagement pin 32 from coming out of the engagement 41.

  Further, a knob 32 a having a hexagonal nut shape is provided at the rear end of the engagement pin 32. By rotating the knob 32a using a hexagon wrench or the like, the engagement pin 32 can be detached from the boss 22d of the rear column frame 22b.

(Maintenance of restraint structure)
To perform maintenance, the cab 5 is lifted upward and is often removed from the base frame 7. At that time, if the restraining structure 30 is provided, the engaging pin 32 becomes an obstacle, and therefore it is necessary to remove the engaging pin 32. If the excavator 1 is a general model, there is a sufficient space behind the cab 5, and therefore the engagement pin 32 can be removed relatively easily.

  However, in the case of the rear small turning type model, the engine room 6 is arranged immediately after the cab 5. In addition, there are counterweights 9 and partition plates 51 that partition the engine room 6. Therefore, it is not easy to remove the engaging pin 32. Therefore, the hydraulic excavator 1 is devised so that the engagement pin 32 can be easily attached and detached.

  In FIG. 8, the counterweight 9 is abbreviate | omitted and the figure which looked at the action part S from the left rear is shown. As shown in the figure, a partition plate 51 for partitioning the engine room 6 is provided behind the cab 5, and the engagement plate 34 is located on the back side of the partition plate 51.

  Therefore, the partition plate 51 is formed with a work opening 52 that is opened to such an extent that the engagement pin 32 can be easily removed. Normally, the work opening 52 is closed by fitting a flexible cup-shaped cover member 53 made of rubber or the like.

  As indicated by phantom lines in FIG. 5, the left end portion of the counterweight 9 is provided so as to be continuous with the left panel member 21 </ b> L of the cab 5 from the viewpoint of design. Therefore, the left end portion of the counterweight 9 is positioned so as to overlap the left and right with the restraint structure 30, but the counterweight 9 is configured to avoid the restraint structure 30.

  As described above, the door cover 9b is provided on the left side of the counterweight 9, so that if the door cover 9b is opened, the work opening 52 can be easily seen, and a sufficient work space is provided. Can be secured.

  Therefore, when the cab 5 is maintained, the door cover 9 b is opened and the cover member 53 is removed from the partition plate 51. Subsequently, the engagement pin 32 is removed from the rear support frame 22b using a hexagon wrench or the like. Then, the engagement pin 32 can be extracted from the engagement hole 41 to the front. If the engaging pin 32 is extracted, the cab 5 can be lifted upward as it is, so that the cab 5 can be easily detached from the base frame 7. When the maintenance is completed, the cab 5 can be easily attached to the base frame 7 by performing the reverse operation of the removal.

(Modification example of restraint structure)
9 and 10 show modified examples of the restraint structure 30. FIG. In these modifications, the structure of the engagement plate 34 is different from that of the above-described embodiment.

  9, the left end fastening seat 15a is provided independently, and the entire engagement plate 34 is directly fixed to the upper surface of the bottom plate 11 by welding. The first reinforcing plate 36a and the second reinforcing plate 36b are also directly fixed to the upper surface of the bottom plate 11 by welding.

  In the modification of FIG. 10, the entire engagement plate 34 is fixed to the upper surface of the left end fastening seat 15a by welding. In any case, since it is not necessary to form a recess for fitting the left end fastening seat 15a in the engagement plate 34, the structure can be simplified.

  In addition, the working machine according to the present invention is not limited to the above-described embodiment, and includes various other configurations.

  For example, the engaging member may be a massive member instead of a plate member. The second reinforcing plate 36 b may also extend above the upper end of the engagement hole 41.

DESCRIPTION OF SYMBOLS 1 Hydraulic excavator 2 Lower traveling body 3 Machine main body 5 Cab 6 Engine room 7 Base frame 11 Bottom plate 13 Side deck 21 Panel member 22 Frame body 22b Rear strut frame (frame member)
23 Door 30 Restraint structure 32 Engagement pin 34 Engagement plate (engagement member)
41 Center of engagement hole A Center axis C

Claims (4)

A work machine having a machine body on a lower traveling body,
The machine body is
A base frame,
A cab installed on the base frame such that a panel member on the door side constitutes one of the left and right side surfaces of the machine body;
A restraint structure that prevents abnormal inclination of the cab;
With
The base frame is
A bottom plate supported by the lower traveling body;
A side deck attached to the bottom plate so as to overhang and supporting the cab via an anti-vibration mount;
Have
The restraint structure is
An engagement pin protruding rearward from the lower rear side of the cab;
An engagement member in which an engagement hole having an inner diameter larger than the outer diameter of the engagement pin is formed;
Have
A work machine in which the engagement pin is inserted into the engagement hole, and the engagement member is fixed to the bottom plate by welding so that the center of the engagement hole coincides with the axis of the engagement pin. The work machine according to claim 1,
The cab has a frame member extending in the vertical direction along the rear edge of the panel member,
The engagement pin is attached to the frame member,
The engagement member is formed of a plate member in which the engagement hole is formed on the front surface and the left and right side ends extend in parallel in the vertical direction.
A work machine in which a center of the engagement hole is formed to be biased toward the side surface of the machine body. The work machine according to claim 2,
Reinforcing plates fixed to the side ends and the bottom plate by welding are provided on the left and right side ends of the engaging member,
A work machine in which the reinforcing plate located on the side of the machine body extends above the upper end of the engagement hole. A working machine according to any one of claims 1 to 3,
An engine room is installed near the rear of the cab,
The engine room has a partition panel that partitions the engine room behind the cab,
The partition panel is formed with a work opening that allows the engagement pin to be extracted from the engagement hole.
A work machine in which a cover member for closing the work opening is detachably attached to the partition panel.

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