JP5065968B2 - Column support member and construction machine cab - Google Patents

Description

  The present invention relates to a column support member and a cab for a construction machine having the column support member, and more particularly to a column support member for supporting a lower portion of a pair of column members and a cab for a construction machine having the column support member.

  2. Description of the Related Art In recent years, cab structures in construction machines are being adopted that can protect the driver when the vehicle falls over, and EOPS (Excavator's Operation Protection Structure) performance is regarded as important. For example, Patent Document 1 discloses a cab structure for a construction machine in which various pipe-shaped members are assembled in a bowl shape to form a frame structure. According to such a structure, the rigidity with respect to a deformation | transformation at the time of a construction machine falling down can be improved significantly compared with the cab structure comprised only by the combination of a sheet metal member.

The above cab structure is formed with an opening for raising and lowering for a driver to get on and off, and a door opening and closing structure for opening and closing the opening is provided.
The door opening / closing structure has a seal structure in order to improve airtightness when closed. The seal member having this seal structure is made of, for example, rubber and is often provided around the lifting opening. However, when a pipe-shaped member is used as a column member, it is difficult to form a flange for attaching a seal member on the column member side. Therefore, as another method, there is also known a structure in which a seal member is attached to a door so that the seal member comes into close contact with the opening for raising and lowering the cab body when the door is closed.
Japanese Patent Laid-Open No. 2003-261064 (released on September 16, 2003)

However, the conventional cab structure has the following problems.
As shown in FIG. 1 and FIG. 2 of Patent Document 1, the lower part of the pillar member is supported by various support members. As these support members, there are a base member that supports the lower end of the column member and a connecting member that extends to connect the base members together. Therefore, the number of parts is increased, and the assembly accuracy of the cab may be lowered because they are connected by welding or the like.

  In Patent Document 1, a reinforcing member (34) for reinforcing a fulcrum portion of a thickened column member is shown as a member that supports the lower portion of the column member. As is apparent from the drawing, the reinforcing member is a generally triangular plate member. The reinforcing member has a plurality of surfaces, and the boundary between the surfaces is formed at a right angle, for example.

  In such a structure, a design in which the sealing member has a curved shape along the boundary portion of the surface of the reinforcing member is conceivable. However, since the boundary between the surfaces of the reinforcing member has a corner, it is considered that the seal member and the member that enters between the two are easily damaged by the force acting from the corner of the reinforcing member. Therefore, such a design is difficult to adopt.

  Therefore, in this case, the sealing member is arranged at the corner formed by the column member and the connecting member of the reinforcing member, and the corner of the sealing member is designed to have a right-angle shape. In order to realize this structure, the oblique end portions of the two sealing members are vulcanized and bonded. However, when vulcanized bonding is used, there is a problem that the cross section becomes non-uniform and water tightness is deteriorated. Therefore, it is not desirable to employ a seal member having a right-angle corner.

  An object of the present invention is to provide a column support member that does not need to adopt a seal member having a right-angle corner and a cab for a construction machine having the column support member.

  A column support member according to a first aspect of the present invention is a column support member that supports a lower portion of a pair of left and right column members among a plurality of column members constituting a cab mounted on a turning frame of a construction machine, and includes a base portion And a connecting portion. The connecting portion is formed integrally with the base portion, and is connected to the lower side surface of the column member. The connecting portion mainly has a plurality of continuous surfaces via curved surfaces, and constitutes a part of a door seal structure provided in the cab.

  Conventionally, the sealing member has a right-angled corner so as to follow a right-angled joint formed by, for example, a column member and a plate member. However, in the present invention, since the connecting portion mainly has each surface continuous through a curved surface, the sealing member is not easily damaged even if a force acts on the sealing member from the connecting portion. Therefore, the load from the seal member can be received by the connecting portion. As a result, it is not necessary to employ a seal member having a right-angle corner.

  A column support member according to a second invention is the column support member according to the first invention, and the connecting portion abuts on a surface of the pair of left and right column members facing the front-rear direction of the pair of left and right column members. ing.

A column support member according to a third invention is the column support member according to the first or second invention, and the support member is a forged or cast part.
Here, since the column support member is a forged or cast product, it is easy to continuously connect a plurality of surfaces of the connecting portion mainly through a curved surface.

A column support member according to a fourth aspect of the present invention is the column support member according to any one of the first to third aspects, wherein the column support member is formed integrally with the connection portion, and left and right from the connection portion. It has a connection part connected with the other pillar support member connected to the other pillar member among a pair of pillar members.
Here, the pair of column members are supported by the pair of column support members. By constituting the column support structure from a pair of column support members, the yield of the column support structure is improved.

A column support member according to a fifth invention is a column support member according to any one of the first to fourth inventions, wherein the pair of left and right column members are a pair of left and right arranged on the front side of the cab. It is a column member.
Here, the lower part of the pair of left and right column members on the front side of the cab and the part that supports it are the parts where stress is most likely to concentrate in the cab. On the other hand, the column support member of the present invention is an integral member, and therefore the strength is improved by separating the weld from the column support member. Therefore, it is significant to apply the column support member of the present invention to the pair of left and right column members on the cab front side.

A cab for construction machinery according to a sixth aspect of the invention includes the column support member according to any one of the first to fifth aspects of the invention.
Here, the number of parts of the cab is reduced by using the above-described column support member.

A construction machine cab according to a seventh aspect is the construction machine cab according to the sixth aspect, wherein the column member is made of a pipe.
Here, since the column member is made of a pipe, it is difficult to form a shape in which two surfaces are mainly continuous via a curved surface at a portion where the lower part of the column member is fixed to the plate member, as compared with other structures. Therefore, the significance of the effect that the load from the seal member can be received by the connecting portion by employing the structure of the present invention is significant.

A construction machine cab according to an eighth invention is the construction machine cab according to the sixth or seventh invention, further comprising a door member. The door member includes a door main body and a seal member that forms a seal structure together with the connecting portion in a state where the door main body is closed.
Here, since the seal member realizes a seal structure together with the connecting portion, it is not necessary to place the seal member along a right-angled portion formed by the column member and the plate, and it is not necessary to vulcanize and bond the end portion of the seal member.

  According to the pillar support member and the cab for construction machinery according to the present invention, since the connecting portion has each surface that mainly continues through the curved surface, the sealing member even if a force acts on the sealing member from the connecting portion. Is hard to break. Therefore, the load from the seal member can be received by the connecting portion. As a result, it is not necessary to employ a seal member having a right-angle corner.

[Configuration of the entire device]
A hydraulic excavator equipped with a column support member according to an embodiment of the present invention and a cab employing the column support member will be described with reference to FIGS.
Note that the terms “left and right”, “front and rear”, and “rear front” used in the following description indicate directions in the cab 10 (see FIG. 1 etc.) that are based on the direction that the operator faces when sitting on a chair. And

[Configuration of hydraulic excavator 1 as a whole]
As shown in FIG. 1, the hydraulic excavator 1 according to the present embodiment mainly includes a lower traveling body 2, a swivel base 3, a work implement 4, a counterweight 5, an engine 6, and a cab 10. ing.

The lower traveling body 2 has the crawler belt P wound around the left and right ends of the traveling direction rotated to move the excavator 1 forward and backward, and the swivel base 3 is mounted on the upper surface side in a swingable state. .
The swivel base 3 can swivel in any direction on the lower traveling body 2, and has a work machine 4, a counterweight 5, an engine 6, and a cab 10 mounted on the upper surface.

  The work implement 4 is configured to include a boom, an arm attached to the tip of the boom, and a bucket attached to the tip of the arm. While moving the arm, bucket, and the like up and down by a hydraulic cylinder, Work at the site of civil engineering work where excavation of earth and sand and gravel.

The counterweight 5 is made of, for example, scrap iron or concrete in a box formed by assembling steel plates and hardened, and is provided at the rear part of the swivel base 3 to balance the vehicle body during mining or the like. ing.
The engine 6 is a drive source for driving the lower traveling body 2 and the work implement 4, and is disposed at a position adjacent to the counterweight 5.

  The cab 10 is a driver's cab in which an operator of the excavator 1 gets on and off, and is disposed on the left front side on the swivel 3 so that the tip of the work machine 4 can be seen. . The cab structure of the cab 10 will be described in detail later.

[Structure of cab 10]
As shown in FIG. 2, the cab 10 is a box-shaped structure for an operator to get on and off, and includes five various column members 11 to 15.
The column members 11 to 15 are the left front column member 11, the right front column member 12, the left rear column member 13, the right rear column member 14, and the left center column member 15.
The left front pillar member 11 and the right front pillar member 12 are so-called A pillars, which are bent in the vicinity of the center portion, and a beam portion constituting a ceiling portion and a pillar portion standing from the floor surface in front of the cab 10. Including.

The left rear pillar member 13 and the right rear pillar member 14 are so-called C pillars, and are erected from the floor behind the cab 10 as substantially linear pillars.
The left central column member 15 is called a so-called B pillar, and is erected from the floor surface at a substantially central portion on the left side surface of the cab 10 or slightly behind it as a substantially linear column.

  The right front column member 12, the right rear column member 14, the left rear column member 13, the left center column member 15, and the left front column member 11 are connected by a floor frame 27. The left front column member 11 and the right front column member 12 are connected by a column support structure 31 (described later). Further, a floor cover 29 is mounted on the floor frame 27 (described later).

Furthermore, although not shown in FIG. 2, the left and right side panels, the ceiling panel, the rear panel, and the bottom panel are attached to the column members 11 to 15 of the cab 10.
Between the left front column member 11 and the left center column member 15 is an entrance / exit 21 of the cab 10, and a door 23 is provided therein as shown in FIG. The door 23 can be opened and closed with a hinge (not shown) as a rotation center.
The cab 10 further includes a seal structure 25 for preventing rainwater and dust from entering the cab 10 from the outside with the doorway 21 of the door 23 closed (described later).

[Cub column support structure]
The left front column member 11 and the right front column member 12 are connected by a column support structure 31. Hereinafter, the column support structure 31 will be described.

As shown in FIG. 3, the column support structure 31 is an elongated member and includes a pair of column support members 33 and 33. The pair of column support members 33 are connected to each other by welding.
The pair of column support members 33, 33 have substantially the same shape. Therefore, hereinafter, only the configuration of the column support member 33 mounted on the left front column member 11 will be described in detail, and detailed description of the configuration of the column support member 33 mounted on the right front column member 12 will be omitted.

  The column support member 33 is a part manufactured by forging or casting, for example. The column support member 33 mainly includes a base portion 33a, a connecting portion 33b, and a contact portion (connecting portion) 33c. The base portion 33 a is a flat plate-like portion fixed on the end portion of the floor frame 27. The connecting portion 33b extends in one direction from the base portion 33a, and the end face of the connecting portion 33b is fixed to the end face of the other connecting portion 33b by welding.

Furthermore, the configuration of the column support member 33 will be described in detail with reference to FIGS.
The contact portion 33c is a wall-like member that is formed integrally with the base portion 33a and rises upward from the end portion of the base portion 33a. More specifically, the contact portion 33 c is formed at the left front end of the base portion, and includes a first contact portion (connection portion) 35 and a second contact portion (connection portion) 37. Yes. The first abutting portion 35 is a plate-like portion extending in the front-rear direction in plan view, and is in contact with the right side surface 11a of the left front pillar member 11 and connected by welding. The second contact portion 37 is a plate-like portion extending to the left side from the rear end of the first contact portion 35 and is in contact with the rear side surface 11b of the left front pillar member 11 and connected by welding. Here, the first contact portion 35 and the second contact portion 37 are in contact with the two surfaces 11a and 11b of the left front column member 11 as reinforcing portions, respectively, thereby improving the strength of the lower portion of the left front column member 11. is doing. Further, since the surfaces of the first contact portion 35 and the second contact portion 37 are smoothly continuous, stress concentration can be reduced in each direction of the left front column member 11.

  Here, since the contact portion 33c and the base portion 33a are integrally formed to constitute the column support member 33, the number of parts is reduced as compared with the conventional case. Because there are few parts, the number of welds is reduced. Therefore, distortion due to welding is reduced and the flatness of the bottom surface of the cab 10 is improved. As a result, the work in the distortion removing process can be reduced.

  Further, the lower part of the pair of left and right column members 11, 12 on the front side of the cab 10 and the part that supports it are the parts where stress is most easily concentrated in the cab 10. On the other hand, the column support member 33 of the present invention is an integral member, so that the welded portion can be separated from the column member 11. Therefore, it is significant to apply the column support member 33 of the present invention to a pair of left and right column members on the cab front side. This is because the strength is improved by separating the welded portion from the column members 11 and 12.

The connecting portion 33b is mainly composed of a plate portion 39 and a step portion 41. The plate portion 39 is a flat portion extending from the base portion 33a. The step portion 41 descends from the upper surface of the first contact portion 35, extends along the plate portion 39, and protrudes upward from the plate portion 39.
The second contact portion 37 will be described in detail. The second contact portion 37 is a structure for supporting the lower portion of the left front pillar member 11 from the side together with the first contact portion 35. The second contact portion 37 has an upper surface 45, a rear side surface 47, and a front end surface 49.

  The upper surface 45 is a surface facing upward, and extends in the left-right direction. The rear side surface 47 is a curved surface that gently descends backward from the upper surface 45 and faces the left rear column member 13 side. The front end surface 49 is smoothly continuous from the rear side surface 47 and faces the left side (outside in the direction in which the column support member 33 extends). The second contact portion 37 further has a front side surface 48 and a lower side surface 50. The front side surface 48 is a substantially flat surface extending in the vertical direction, and abuts on the side surface 11b on the rear side of the left front column member 11. The lower side surface 50 abuts on the upper surface of the floor frame 27. The front end surface 49 is formed by an upper surface 45, a rear side surface 47, and surfaces 48 and 50 on the opposite side thereof. Each surface, such as the upper surface 45, the rear side surface 47, and the front end surface 49, is continuous with each other via a curved surface. In other words, no corner is formed at the boundary between the surfaces.

The welding locations of the column support member 33 to the left front column member 11 are only locations along the upper surface of the first contact portion 35 and the upper surface 45 of the second contact portion 37 of the contact portion 33c. Thus, the flatness of the bottom surface of the cab 10 is improved by minimizing the number of welds.
Further, the connecting portions 33b of the pair of column support members 33 are welded with their front end surfaces in contact with each other. Since the connecting portions 33b of the pair of column support members 33 are connected at the approximate center between the pair of left and right column members of the cab, the welding location is farthest from both the column members 11 and 12 and the contact portion 33c. Therefore, distortion due to welding hardly affects the lower portions of the pair of column members 11 and 12, the contact portion 33 c of the column support member 33, and the like. Therefore, the flatness of the bottom surface of the cab 10 is further improved.

  As shown in FIG. 12, the end of the floor cover 29 is disposed above the column support member 33. Further, a part of the end portion of the floor cover 29 has a cover portion 29 a, and the cover portion 29 a is close to the front end surface 49 of the second contact portion 37 of the contact portion 33 c of the column support member 33. Yes.

[Structure of seal part]
The seal structure 25 mainly includes a seal member 51 and other members that come into contact with the seal member 51 when the door 23 is closed. The seal member 51 is disposed along substantially the entire edge of the door 23.
As shown in FIGS. 8 to 10, the corner on the lower front side of the seal member 51 is a curved corner 51 a that is smoothly curved. In a state where the door 23 is closed, the curved corner portion 51 a of the seal member 51 extends along the front end surface 49 of the column support member 33 with the cover portion 29 a of the floor cover 29 interposed therebetween. Thereby, the load from the curved corner portion 51 a of the seal member 51 is mainly received by the distal end surface 49 of the column support member 33. The curved corner 51a of the seal member 51 applies a load to the edge of the floor frame 27 and the edge of the left front pillar member 11. As described above, with the door 23 closed, the curved corner 51 a of the seal member 51 mainly realizes a part of the seal structure 25 together with the tip surface 49.

  The realization of the seal structure 25 by the seal member 51 and the column support member 33 will be described in more detail. The contact portion 33 c has a plurality of smoothly continuous surfaces 45 to 50 and constitutes a part of the seal structure 25 of the door 23. More specifically, the seal structure 25 is configured by the surfaces of the seal member 51 and the second contact portion 37. Conventionally, the seal member has a right-angled corner so as to follow a right-angled joint formed by the left front pillar member 11 and the floor frame 27, for example. However, in the present invention, the contact portion 33c has smoothly continuous surfaces 45 to 50. Therefore, a force acts on the seal member 51 and the cover portion 29a of the floor cover 29 therebetween from the contact portion 33c. However, the seal member 51 and the floor cover 29 are not easily damaged. More specifically, even if a force acts on the seal member 51 from the boundary portion between the rear side surface 47 and the front end surface 49 of the second contact portion 37 or the boundary portion between the upper surface 45 and the front end surface 49, the second contact Since the rear side surface 47 and the front end surface 49 of the contact portion 37 are smoothly continuous, the possibility of damage to the seal member 51 and the floor cover 29 is low. Therefore, the load from the seal member 51 can be received by the contact portion 33c. As a result, it is not necessary to place the seal member along a right-angled corner formed by the left front pillar member 11 and the floor frame 27. As a result, it is not necessary to employ a seal member using vulcanization adhesion, and therefore, water tightness is improved and the manufacturing cost of the seal member can be reduced.

In this configuration, since the column support member 33 is a forged product or a cast product, it is easy to smoothly connect the plurality of surfaces 47 to 50 of the contact portion 33c.
In particular, since the pillar members 11, 12 and the like of the cab 10 are made of pipe, compared to the case where the press material is used for the pillar, the two surfaces smoothly continue to the portion where the lower part of the pillar member is fixed to the floor frame. It is difficult to form a shape. For this reason, the significance of the effect obtained by adopting the structure of the present invention (the surfaces of the members that receive the load of the sealing member smoothly continue) is significant.

  As described above, by collecting members by forging, reduction of small articles and reduction of welded parts are realized. Furthermore, the stress concentration is eased by making the reinforcing part a smooth shape. Moreover, the stress concentration is eased with respect to the front-rear direction and the left-right direction of the fulcrum portion by forming the reinforcing portion so as to rise along the pair of column members.

[Other Embodiments]
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of invention.
In the above embodiment, the column support structure supports the pair of left and right column members on the front side of the cab. However, this may be used to support the pair of left and right column members on the rear side of the cab.

In the present embodiment, a hydraulic excavator has been described as an example, but the present invention can also be applied to a construction machine (wheel loader, bulldozer, etc.) other than the hydraulic excavator.
In the said embodiment, the contact part 33c of the pillar support member 33 and the detailed example of the seal structure 25 were mentioned and demonstrated. However, the present invention is not limited to this.

  The column support member of the present invention has an effect that it is not necessary to employ a seal member having a right-angled corner portion because the connection portion has each surface mainly connected through a curved surface. Widely applicable to machine cabs.

1 is a schematic side view of a hydraulic excavator in which a cab according to an embodiment of the present invention is employed. The perspective view of the cab in the state which removed the panel and the door. The perspective view of the support structure concerning one embodiment of the present invention. The top view of the support structure which concerns on one Embodiment of this invention. The top view of the supporting member which concerns on one Embodiment of this invention. The front view of the supporting member which concerns on one Embodiment of this invention. The perspective view of the lower end part of a 1st pillar member, and a part of support member. The perspective view of a seal structure. The perspective view of a seal structure. The front view of a seal structure. XI-XI arrow sectional drawing of FIG. XII-XII arrow sectional drawing of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hydraulic excavator 2 Undercarriage 3 Swing stand 4 Working machine 5 Counterweight 6 Engine 10 Cab 11 Left front pillar member 12 Right front pillar member 13 Left rear pillar member 14 Right rear pillar member 15 Left center pillar member 21 Entrance 23 Door 25 Seal structure 27 Floor frame 29 Floor cover 29a Cover portion 31 Column support mechanism 33 Column support member 33a Base portion 33b Connection portion 33c Contact portion (connection portion)
35 1st contact part (1st connection part)
37 2nd contact part (2nd connection part)
39 Plate part 41 Step part 45 Upper surface 47 Rear side surface 48 Front side surface 49 Front end surface 50 Lower side surface 51 Seal member 51a Curved corner

Claims (8)

A column support member that supports the lower part of a pair of left and right column members among a plurality of column members constituting a cab mounted on a turning frame of a construction machine,
A base part;
A connecting portion formed integrally with the base portion and connected to a lower side surface of the pillar member;
The connecting portion has a plurality of continuous surfaces via a curved surface, and constitutes a part of a door seal structure provided in the cab.
Column support member.   2. The column support member according to claim 1, wherein the connection portion is connected to a surface facing the front-rear direction of the pair of left and right column members in one of the pair of left and right column members.   The column support member according to claim 1, wherein the column support member is a forged or cast part.   The column support member is formed integrally with the connection portion, and has a connection portion that is connected to the other column support member connected to the other column member from the connection portion to the other column member. The column support member according to any one of claims 1 to 3.   5. The column support member according to claim 1, wherein the pair of left and right column members is a pair of left and right column members disposed on a front side of the cab. The column support member according to any one of claims 1 to 5,
A cab for construction machinery equipped.   The cab for construction machinery according to claim 6, wherein the pillar member is made of a pipe. A door member,
The cab for a construction machine according to claim 6 or 7, wherein the door member includes a door main body and a seal member that forms a seal structure together with the connecting portion in a state where the door main body is closed.

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