AU2022434213A1 - Front loader - Google Patents

Abstract

The present invention provides a front loader with which visibility can be improved.　The front loader comprises a boom 30 in which an internal space S30 is formed, and a side frame a side frame 20 that swingably supports the boom 30 and has formed therein a first opening 23 through which a pipe part 90 for forming a hydraulic oil flow path can be inserted. A first opening part is formed in one side surface of the side frame 20 in the left-right direction, and a second opening part 24 through which the pipe part 90 can be inserted is formed in the surface of the side frame 20 opposite from the boom 30.

Description

DESCRIPTION TITLE OF INVENTION: FRONT LOADER TECHNICAL FIELD

[0001]

The present invention relates to a technique of a front loader capable of

operating a working tool coupled to a boom with hydraulic oil.

BACKGROUNDART

[0002]

Conventionally, a technique of a front loader capable of operating a

working tool coupled to a boom with hydraulic oil is known. For example,

Patent Literature 1 discloses such a technique.

[0003]

The front loader described in Patent Literature 1 includes a sub frame

(side frame), a lift arm (boom) rockably supported by the sub frame, a hydraulic

hose that guides hydraulic oil used in various hydraulic cylinders, and the like.

[0004]

The hydraulic hose described in Patent Literature 1 is provided along one

of left and right side surfaces of the sub frame and the lift arm in order to guide

hydraulic oil to a hydraulic cylinder provided at a front portion of the lift arm.

However, in this case, since the hydraulic hose is exposed to a side of the sub

frame and the lift arm, there is a possibility that the hydraulic hose blocks a field

of view of an operator and the visibility is deteriorated.

CITATION LIST PATENT LITERATURE

[0005]

Patent Literature 1: JP H11-241361 A

SUMMARY OF INVENTION TECHNICAL PROBLEM

[0006]

One aspect of the present disclosure has been made in view of the above

circumstances, and an object of the present disclosure is to provide a front loader

capable of improving visibility.

SOLUTION TO PROBLEM

[0007]

The problem to be solved by one aspect of the present disclosure is as

described above, and means for solving the problem will be described below.

[0008]

That is, one aspect of the present disclosure includes: a boom; and a side

frame rockably supporting the boom and formed with a first opening through

which a tube portion forming a flow path for hydraulic oil can be inserted.

According to one aspect of the present disclosure, since the tube portion

can be disposed in the side frame, it is possible to suppress the tube portion from

blocking the field of view of the operator.

[0009]

In one aspect of the present disclosure, the first opening is formed on one

side surface of the side frame in a left-right direction.

According to one aspect of the present disclosure, the tube portion can be

introduced into the side frame from the left and right outer sides of the side

frame.

[0010]

In one aspect of the present disclosure, a second opening through which

the tube portion can be inserted is formed on a surface of the side frame facing

the boom.

According to one aspect of the present disclosure, the tube portion can be

led out from the inside of the side frame toward the boom.

[0011]

In one aspect of the present disclosure, the boom is formed with: a third

opening that is formed on a surface facing the side frame and through which the

tube portion can be inserted; and a fourth opening different from the third

opening.

According to one aspect of the present disclosure, it is possible to

effectively suppress the tube portion from blocking the field of view of the

operator, and thus, it is possible to effectively improve the visibility.

[0012]

An aspect of the present disclosure further includes a coupling frame that

couples the boom on a right side and the boom on a left side, in which the tube

portion is led out from an inside of the boom to the coupling frame through the

fourth opening, branched on the coupling frame, and connected to left and right

boom cylinders and left and right bucket cylinders.

According to one aspect of the present disclosure, since branch portions of

the tube portion can be gathered on the coupling frame, assembling and

maintenance of the tube portion can be easily performed.

[0013]

An aspect of the present disclosure further includes a first cover that

covers the tube portion on the coupling frame.

According to one aspect of the present disclosure, the tube portion on the

coupling frame can be hidden by the first cover, and the aesthetic appearance can

be improved.

[0014]

In one aspect of the present disclosure, an opening is formed in the first

cover.

According to one aspect of the present disclosure, hydraulic pressure can

be utilized through the opening.

[0015]

An aspect of the present disclosure further includes a second cover that

covers the fourth opening.

According to one aspect of the present disclosure, the fourth opening and

the tube portion led out from the fourth opening can be hidden by the second

cover, and the aesthetic appearance can be improved.

[0016]

In one aspect of the present disclosure, an attitude maintenance

mechanism can be attached to the boom, the attitude maintenance mechanism

being configured to maintain an attitude of a working tool coupled to the boom by

operating according to rocking of the boom, and the boom includes: an

attachment portion at least a part of which is disposed inside the boom and that

attaches the attitude maintenance mechanism; and a guide portion at least a

part of which is disposed inside the boom and that guides the tube portion so as

to avoid the attachment portion.

According to one aspect of the present disclosure, the tube portion is

easily disposed in the boom by guiding the tube portion by the guide portion.

ADVANTAGEOUS EFFECTS OF INVENTION

[0017]

According to one aspect of the present disclosure, visibility can be

improved.

BRIEF DESCRIPTION OF DRAWINGS

[0018]

Fig. 1 is a side view illustrating an overall configuration of a tractor

including a front loader according to an embodiment of the present invention.

Fig. 2 is a perspective view illustrating the front loader.

Fig. 3 is a left side view of the same.

Fig. 4 is a right side cross-sectional view of the same.

Fig. 5 is a front view illustrating a coupling frame and a tube portion.

Fig. 6(a) is a left side view illustrating a side frame. Fig. 6(b) is a left

side view illustrating the inside of the side frame.

Fig. 7 is an exploded perspective view of a boom.

Fig. 8 is a right side cross-sectional view illustrating the side frame and

the boom.

Fig. 9 is a cross-sectional view taken along line Al-Al.

Fig. 10 is a right side cross-sectional view of the front loader

schematically illustrating the tube portion.

Fig. 11(a) is a front cross-sectional view schematically illustrating a first

tube portion on the coupling frame. Fig. 11(b) is a front cross-sectional view

schematically illustrating a second tube portion on the coupling frame.

Fig. 12 is a cross-sectional view taken along line A2-A2.

Fig. 13 is a partial rear cross-sectional view schematically illustrating the first tube portion and a third tube portion.

Fig. 14 is a right side cross-sectional view of the front loader

schematically illustrating the third tube portion.

Fig. 15(a) is a front view illustrating a cover. Fig. 15(b) is a cross

sectional view taken along line A3-A3.

DESCRIPTION OF EMBODIMENT

[0019]

In the following description, directions indicated by arrows U, D, F, B, L,

and R in the drawings are defined as an upward direction, a downward direction,

a forward direction, a backward direction, a left direction, and a right direction,

respectively.

[0020]

Hereinafter, the entire configuration of a tractor 1 including a front

loader 10 according to one embodiment of the present invention will be described.

[0021]

As illustrated in Fig. 1, the tractor 1 mainly includes a machine body

frame 2, an engine 3, a transmission case 4, front wheels 5, rear wheels 6, a

bonnet 7, a cabin 8, a steering wheel 9, and a front loader 10.

[0022]

The machine body frame 2 is a frame-shaped member formed by

appropriately combining a plurality of panel members. The machine body frame

2 is formed in a substantially rectangular shape in plan view. The machine

body frame 2 is disposed with its longitudinal direction oriented in a front-rear

direction. The engine 3 is fixed to a rear portion of the machine body frame 2.

The transmission case 4 is fixed to a rear portion of the engine 3. A front portion of the machine body frame 2 is supported by the pair of left and right front wheels 5 through a front axle mechanism (not illustrated). A rear portion of the transmission case 4 is supported by the pair of left and right rear wheels 6 through a rear axle mechanism (not illustrated). The engine 3 is covered with the bonnet 7.

[0023]

Power of the engine 3 can be transmitted to the front wheels 5 through

the front axle mechanism and can be transmitted to the rear wheels 6 through

the rear axle mechanism after being shifted by a transmission device (not

illustrated) stored in the transmission case 4. The front wheels 5 and the rear

wheels 6 are rotationally driven by the power of the engine 3, and the tractor 1

can travel.

[0024]

The cabin 8 is provided behind the engine 3. Inside the cabin 8, a living

space on which an operator boards is formed. In the living space, the steering

wheel 9 for adjusting a turning angle of the front wheels 5, various operation

tools, a seat on which the operator sits, and the like are disposed.

[0025]

The front loader 10 is mounted to a front portion of the tractor 1.

Hereinafter, the configuration of the front loader 10 will be briefly described with

reference to Figs. 2 to 5.

[0026]

As illustrated in Figs. 2 and 3, the front loader 10 mainly includes a side

frame 20, a boom 30, a coupling frame 40, a bucket 50, a stand 60, a boom

cylinder 70, a bucket cylinder 80, a tube portion 90, a cover 100, an attitude maintenance mechanism 110, and the like.

[0027]

The side frame 20 rockably supports the boom 30 described later. The

side frame 20 is detachably attached to a vehicle body (the machine body frame 2

and the transmission case 4) of the tractor 1. The side frames 20 are provided

on the left and right of the vehicle body. A detailed configuration of the side

frames 20 will be described later.

[0028]

The booms 30 are rockably supported by the left and right side frames 20.

The boom 30 is disposed so as to extend forward and downward from an upper

portion of the side frame 20. A detailed configuration of the boom 30 will be

described later.

[0029]

The coupling frame 40 couples the left and right booms 30. The coupling

frame 40 is formed in a substantially cylindrical shape with its axis oriented to

the left and right. The coupling frame 40 is provided across the left and right

booms 30.

[0030]

The bucket 50 is formed to open forward. The bucket 50 is rockably

coupled to the front end of the boom 30.

[0031]

The stand 60 allows the front loader 10 detached from the vehicle body of

the tractor 1 to stand by itself. One stand 60 (a pair of right and left stands) is

provided at each lower front portion of the right and left booms 30. The stand

can be switched between a storage position where the stand is stored in the boom 30 and a support position where the stand is grounded to support the weight of the front loader 10. Note that the stand 60 switched to the storage position is illustrated in the drawings.

[0032]

The boom cylinder 70 rocks the boom 30 with respect to the side frame 20.

The boom cylinder 70 is rockably coupled to the side frame 20 and the boom 30.

A pair of the left and right boom cylinders 70 is provided.

[0033]

The bucket cylinder 80 rocks the bucket 50 with respect to the boom 30.

The bucket cylinder 80 is rockably coupled to the boom 30 and the bucket 50.

The bucket cylinder 80 of the present embodiment is rockably coupled to the

boom 30 through a second link member 113 of the attitude maintenance

mechanism 110 described later. A pair of the left and right bucket cylinders 80

is provided.

[0034]

The tube portion 90 illustrated in Figs. 3 to 5 is for forming a flow path of

hydraulic oil. The tube portion 90 connects a hydraulic pump (not illustrated)

driven by the engine 3, the boom cylinder 70, and the like. The cover 100 is a

member that covers the tube portion 90 (see Fig. 2). Detailed configurations of

the tube portion 90 and the cover 100 will be described later.

[0035]

The attitude maintenance mechanism 110 illustrated in Figs. 2 and 3

operates according to rocking of the boom 30 to maintain an attitude of the

bucket 50 (working tool). A pair of the left and right attitude maintenance

mechanisms 110 is provided. Since the left and right attitude maintenance mechanisms 110 have substantially the same configuration, the configuration of the attitude maintenance mechanism 110 will be described by taking the attitude maintenance mechanism 110 on the left side as an example, and the description of the configuration of the attitude maintenance mechanism 110 on the right side will be omitted. The attitude maintenance mechanism 110 includes a fixing member 111, a first link member 112, and a second link member 113.

[0036]

The fixing member 111 is a member that is fixed to an upper portion of

the side frame 20 and supports a rear portion of the first link member 112.

[0037]

The first link member 112 is a member provided between the fixing

member 111 and the second link member 113. The first link member 112 is

formed in a longitudinal shape extending substantially in the front-rear

direction. A rear end portion of the first link member 112 is rockably coupled to

the fixing member 111. In this way, the first link member 112 can rock with

respect to the fixing member 111 with the left-right direction as an axial

direction. A rock fulcrum of the first link member 112 with respect to the fixing

member 111 is disposed at a position different from a rock fulcrum of the boom 30

in a side view.

[0038]

The second link member 113 is a member coupled to the bucket cylinder

and the first link member 112. The second link member 113 is formed in a

plate shape with a plate surface facing substantially the left-right direction.

The second link member 113 is formed in a substantially triangular shape in a

side view. A lower end portion of the second link member 113 is rockably supported by the boom 30 through a substantially columnar coupling portion

113a whose axis is directed to the left and right. Furthermore, the second link

member 113 is coupled to the first link member 112 and the bucket cylinder 80

through substantially columnar coupling portions 113b and 113c whose axes are

directed to the left and right.

[0039]

The boom 30 of the front loader 10 configured as described above is

rocked with respect to the side frame 20 according to expansion and contraction

of the boom cylinder 70. Thus, the boom 30 is raised and lowered. The first

link member 112 and the second link member 113 are rocked as the boom 30

moves up and down. The attitude maintenance mechanism 110 can maintain

the attitude of the bucket 50 by rocking of the link members 112 and 113 without

allowing the operator to expand and contract the bucket cylinder 80.

[0040]

Hereinafter, details of the left and right side frames 20 will be described

with reference to Figs. 6 and 7. First, the right side frame 20 will be described.

The right side frame 20 includes a side surface portion 21, a connection portion

22, a first opening 23, and a second opening 24.

[0041]

The side surface portion 21 forms left and right side surfaces of the side

frame 20. The side surface portion 21 is formed in a plate shape with a plate

surface facing substantially the left-right direction. The side surface portions 21

are disposed at intervals in the left and right.

[0042]

The connection portion 22 connects the left and right side surface portions

21. The connection portion 22 is formed in a substantially rectangular annular

shape in a side view. A space surrounded by the side surface portions 21 and

the connection portion 22 is an internal space S20 of the side frame 20.

[0043]

The first opening 23 is a portion through which the tube portion 90

described later can be inserted. The first opening 23 is formed so as to penetrate

the left side surface portion 21 in the left-right direction. Thus, the first opening

23 is formed on the left side surface of the side frame 20. The first opening 23

communicates with the internal space S20 of the side frame 20. The first

opening 23 is formed in a substantially quadrangular shape in a side view.

[0044]

The second opening 24 illustrated in Fig. 6(b) is a portion through which

the tube portion 90 can be inserted. The second opening 24 is formed so as to

penetrate the upper portion of the connection portion 22. The second opening 24

is formed above first opening 23 (on a side of the boom 30). The second opening

24 communicates with the internal space S20 of the side frame 20.

[0045]

The left side frame 20 is configured similarly to the right side frame 20

except that the first opening 23 and the second opening 24 are not provided.

[0046]

Hereinafter, the left and right booms 30 will be described in detail with

reference to Figs. 3 and 7 to 9. First, the right boom 30 will be described. As

illustrated in Figs. 3 and 7, the boom 30 includes a boom frame 31, a boss portion

32, a guide portion 33, a closing portion 34, and a side plate 35.

[0047]

The boom frame 31 forms a main structural body of the boom 30. As

illustrated in Figs. 8 and 9, the boom frame 31 is formed in a hollow shape

having an internal space S30 surrounded by an upper surface 31a, left and right

side surfaces 31b, and a bottom surface 31c. Lower end portions of the left and

right side surfaces 30b are formed so as to protrude downward from the bottom

surface 30a of the boom 30. In this way, a space surrounded by the left and

right side surfaces 31b and the bottom surface 31c is formed in a lower portion of

the boom frame 31. Hereinafter, the space is referred to as a "storage space

S31". The storage space S31 is formed over both ends in the longitudinal

direction of the boom frame 31. As illustrated in Figs. 7 to 9, the boom frame 31

includes a third opening 31d, a through hole 31e, a slit 31f, a fourth opening 31g,

and a cutout portion 31h.

[0048]

The third opening 31d illustrated in Fig. 8 is a portion through which the

tube portion 90 can be inserted. The third opening 31d is formed at a rear end

of the bottom surface 31c. The third opening 31d allows the outside of the boom

frame 31 to communicate with the internal space S30.

[0049]

The through hole 31e illustrated in Figs. 7 and 8 is a hole penetrating the

upper surface 31a of the boom frame 31. The through hole 31e is formed at a

front-rear middle portion of the upper surface 31a.

[0050]

The slit 31f is a horizontally long hole penetrating the boom frame 31 in

the left-right direction. The slits 31f are formed on the left and right side

surfaces 31b. Each of the slits 31f is formed below the through hole 31e.

[0051]

The fourth opening 31g is a portion through which the tube portion 90

can be inserted. The fourth opening 31g is formed so as to penetrate the left

side surface 31b in the left-right direction. The fourth opening 31g is formed in

a substantially elliptical shape in a side view. The fourth opening 31g is formed

on the front lower side (a side of the bucket 50) of the through hole 31e.

Furthermore, the fourth opening 31g is formed on the rear upper side of the

coupling frame 40 in a side view.

[0052]

The cutout portion 31h illustrated in Figs. 8 and 9 is formed in the left

side surface 31b. The cutout portion 31h is formed in a recessed shape in which

an end portion of the side surface 31b is cut out. The cutout portion 31h is

formed in a rear portion and a front portion of the side surface 31b. The rear

cutout portion 31h is formed between the third opening 31d and the slit 31f in a

side view. The front cut out portion 31h is formed below the fourth opening 31g

and behind the coupling frame 40 in a side view.

[0053]

As illustrated in Figs. 7 and 8, the rear end portion of the boom frame 31

configured as described above is disposed between the side surface portions 21 of

the side frame 20 and coupled to the side surface portions 21. Accordingly, the

boom frame 31 is supported by the side frame 20. The bottom surface 31c of the

boom frame 31 faces the connection portion 22 of the side frame 20. As

described above, the second opening 24 of the present embodiment is formed on a

surface (the connection portion 22) of the side frame 20 facing the boom 30.

Furthermore, the third opening 31d is formed on a surface of the boom 30 facing the side frame 20 (bottom surface 31c).

[0054]

The boss portion 32 is for attaching the second link member 113 of the

attitude maintenance mechanism 110. The boss portion 32 is formedin a

substantially cylindrical shape with an axis line facing the left and right. A

length of the boss portion 32 in the axial direction is formed to be longer than a

left-right width of the boom frame 31. The boss portion 32 is provided so as to

penetrate the left and right side surfaces 31b. In this way, the boss portion 32 is

provided so as to cross the internal space S30 of the boom 30. The boss portion

32 is fixed to the side surfaces 31b of the boom frame 31 by welding or the like.

[0055]

The coupling portion 113a that couples the boom frame 31 and the second

link member 113 is inserted into the boss portion 32. As described above, in the

present embodiment, the second link member 113 is supported by the boss

portion 32 crossing the internal space S30 of the boom 30. Accordingly, the

second link member 113 can be disposed at a relatively low position. Therefore,

it is possible to suppress the second link member 113 from greatly protruding

upward from the boom 30 and to suppress the second link member 113 from

blocking the field of view of the operator.

[0056]

The guide portion 33 is for guiding the tube portion 90 described later.

The guide portion 33 is formed in a plate shape with a plate surface facing

substantially the vertical direction. A left-right width of the guide portion 33 is

formed to be substantially equal to the left-right width of the boom frame 31.

The guide portion 33 is fixed to the left and right slits 31f by welding or the like.

In this manner, substantially the entire guide portion 33 is disposed inside the

boom 30. Furthermore, the guide portion 33 is provided so as to extend between

the boss portion 32 and the bottom surface 31c of the boom frame 31. More

specifically, the guide portion 33 is provided so as to extend rearward from the

vicinity of a top portion of the boss portion 32 to approach the bottom surface 31c

of the boom frame 31 and have a rear end portion located in the vicinity of the

bottom surface 31c so as to guide the tube portion 90 upward of the boss portion

32.

[0057]

The closing portion 34 is a plate-shaped member that closes the through

hole 31e of the boom frame 31. The closing portion 34 is fixed to the boom frame

31 after the boss portion 32 and the guide portion 33 are fixed to the boom frame

31. As a result, the boss portion 32 and the guide portion 33 can be easily

welded to the inside of the boom frame 31 through the through hole 31e.

[0058]

The side plate 35 is formed in a plate shape with a plate surface facing

substantially the left-right direction. The side plates 35 are provided on the left

and right of the boom frame 31. The left and right side plates 35 are fixed to a

front-rear middle portion of the boom frame 31.

[0059]

The left boom 30 is configured similarly to the right boom 30 except that

the third opening 31d, the slit 31f, the fourth opening 31g, the rear cutout portion

31h, and the guide portion 33 are not provided.

[0060]

Hereinafter, the configuration of the tube portion 90 will be described with reference to Figs. 4, 5, and 10 to 14. Note that, in Figs. 10 to 14, the tube portion 90 is schematically illustrated for convenience. The tube portion 90 is formed by appropriately connecting a metal pipe and a flexible hose. As illustrated in Figs. 4 and 5, the tube portion 90 includes a first tube portion 91, a second tube portion 92, and a third tube portion 93.

[0061]

The first tube portion 91 connects a hydraulic pump driven by the engine

3 and the boom cylinder 70. Note that the boom cylinder 70 of the present

embodiment is provided with two ports (a first port and a second port). The first

tube portion 91 connects these two ports and the hydraulic pump. That is, the

first tube portion 91 includes a total of two tube portions including a tube portion

connecting the hydraulic pump and the first port and a tube portion connecting

the hydraulic pump and the second port. As illustrated in Figs. 10 and 11(a),

the first tube portion 91 is connected to the boom cylinder 70 after passing

through the side frame 20 and the internal spaces S20 and S30 of the boom 30.

Hereinafter, a specific description will be given. Note that, in Figs. 10 to 12, the

two first tube portions 91 are indicated by one line.

[0062]

As illustrated in Fig. 10, the first tube portion 91 is introduced from the

hydraulic pump into the side frame 20 through the first opening 23. The first

tube portion 91 is led out from the internal space S20 of the side frame 20 to the

outside of the side frame 20 through the second opening 24, and is introduced

into the boom frame 31 through the third opening 31d. The first tube portion 91

introduced into the boom frame 31 extends toward the fourth opening 31g in the

internal space S30 of the boom 30.

[0063]

Here, the boom 30 is provided with the boss portion 32 that crosses the

internal space S30. For this reason, when the first tube portion 91 is assembled,

if the first tube portion 91 is fed out from the third opening 31d toward the fourth

opening 31g, the boss portion 32 becomes an obstacle, and there is a concern that

it becomes difficult to assemble the first tube portion 91. Therefore, in the

present embodiment, the guide portion 33 is provided so that the tube portion 90

can be guided to the upper side of the boss portion 32. The guide portion 33 can

guide the first tube portion 91 and the second tube portion 92 to the fourth

opening 31g so as to avoid the boss portion 32 (pass above the boss portion 32).

As a result, it is possible to suppress the boss portion 32 from being an obstacle

when the first tube portion 91 is provided, and to easily dispose the first tube

portion 91 in the boom 30.

[0064]

As illustrated in Figs. 10 to 12, the first tube portion 91 having passed

through the boss portion 32 is led out from the internal space S30 of the boom

frame 31 onto the coupling frame 40 through the fourth opening 31g.

[0065]

As described above, the first tube portion 91 of the present embodiment is

disposed in the side frame 20 and the boom frame 31 from the first opening 23 to

the fourth opening 31g. As a result, it is possible to suppress the first tube

portion 91 from blocking the field of view of the operator, and thus, visibility can

be improved. Furthermore, by improving the visibility, the work by the front

loader 10 can be easily performed, and the workability can also be improved.

Furthermore, the first tube portion 91 can be hidden by the side frame 20 and the boom frame 31, and the aesthetic appearance can be improved. Furthermore, even if the first tube portion 91 is damaged by any chance, it is possible to prevent the hydraulic oil from scattering in a wide range.

[0066]

In particular, in the present embodiment, the first tube portion 91 is

introduced into the side frame 20 from the first opening 23. As a result, it is

difficult for the hose to be exposed to the side of the side frame 20 and the boom

frame 31, and it is possible to effectively prevent the first tube portion 91 from

blocking the field of view of the operator.

[0067]

Furthermore, in a case where the attitude maintenance mechanism 110

(see Fig. 3) that operates according to the rocking of the boom 30 is provided as in

the present embodiment, the first tube portion 91 is disposed in the side frame 20

and the boom 30, so that the attitude maintenance mechanism 110 can be

prevented from interfering with the first tube portion 91 and being damaged.

[0068]

As illustrated in Fig. 11(a), the first tube portion 91 led out onto the

coupling frame 40 is branched by a branch portion 91a provided on the coupling

frame 40. Note that, although not illustrated in Fig. 11(a), two branch portions

91a (the same number as the first tube portions 91) are provided. The branch

portions 91a are disposed so as to be shifted from each other in the left-right

direction.

[0069]

The first tube portion 91 branched by the branch portion 91a extends

toward the left and right boom frames 31. As illustrated in Figs. 12 and 13, the first tube portion 91 is introduced into the storage space S31 through the front cutout portion 31h. As illustrated in Figs. 10 and 13, the first tube portion 91 extends rearward and upward in the storage space S31. Thus, the first tube portion 91 is guided from the coupling frame 40 to the vicinity of the right and left boom cylinders 70. The first tube portion 91 is connected to the right and left boom cylinders 70.

[0070]

As described above, the first tube portion 91 of the present embodiment is

disposed in the storage space S31 from the front cutout portion 31h to the vicinity

of the boom cylinder 70. With such a configuration, the first tube portion 91 can

be hidden in the storage space S31 to make the first tube portion 91 less visible,

and visibility can be improved. Furthermore, even if the first tube portion 91 is

damaged by any chance, it is possible to prevent the hydraulic oil from scattering

in a wide range.

[0071]

Furthermore, the first tube portion 91 branched by the branch portion

91a is constituted by a pipe 91b made of metal except for a part thereof.

Specifically, the first tube portion 91 is constituted by the pipe 91b made of metal

except for the vicinities of the left and right boom cylinders 70 (from the lower

side of the boss portion 32 to the upper side of the front end portion of the boom

cylinder 70 in a side view). Furthermore, in the first tube portion 91, a portion

(near the boom cylinder 70) other than the metal pipe 91b is constituted by a

hose 91c having flexibility.

[0072]

Since the first tube portion 91 is constituted by the pipe 91b made of metal except for a part thereof in this manner, a length of the hose 91c can be shortened to suppress the sagging of the first tube portion 91. As a result, it is possible to suppress the first tube portion 91 from being exposed to the outside and to suppress deterioration in appearance.

[0073]

The second tube portion 92 connects the hydraulic pump and the bucket

cylinder 80. Note that the bucket cylinder 80 of the present embodiment is

provided with two ports (a first port and a second port). The second tube portion

92 connects these two ports and the hydraulic pump. That is, the second tube

portion 92 includes a total of two tube portions including a tube portion

connecting the hydraulic pump and the first port and a tube portion connecting

the hydraulic pump and the second port. As illustrated in Figs. 10 and 11(b),

similarly to the first tube portion 91, the second tube portion 92 is led out onto

the coupling frame 40 through the side frame 20 and the internal spaces S20 and

S30 of the boom 30. Note that, in Figs. 10 to 13, the two second tube portions 92

are indicated by one line.

[0074]

As illustrated in Fig. 11(b), the second tube portion 92 is branched by a

branch portion 92a provided on the coupling frame 40. Note that, although not

illustrated in Fig. 11(b), two branch portions 92a (the same number as the second

tube portions 92) are provided. The branch portions 92a are disposed so as to be

shifted from each other in the left-right direction. Furthermore, the branch

portion 92a is disposed to be shifted in position in the left-right direction with

respect to the branch portion 91a of the first tube portion 91. In this way, in the

present embodiment, all the branch portions 91a and 92a are disposed with their positions shifted from each other in the left-right direction.

[0075]

The second tube portion 92 branched by the branch portion 92a extends

toward the left and right boom frames 31. The second tube portion 92 extends

substantially upward along the side surface 31b of the boom frame 31 and is

connected to the left and right bucket cylinders 80 (see Figs. 2 and 13).

[0076]

The third tube portion 93 is for connecting a device (for example, a snow

blower, a snow blade, a sweeper, and the like.) different from the boom cylinder

and the bucket cylinder 80 to the hydraulic pump. Similarly to the first tube

portion 91, the third tube portion 93 includes two tube portions. Note that, in

Figs. 13 and 14, the two third tube portions 93 are indicated by one line.

[0077]

As illustrated in Fig. 14, the third tube portion 93 extends from the

hydraulic pump along the left side surface of the side frame 20 and the boom 30.

The third tube portion 93 is introduced into the storage space S31 through the

cutout portion 31h on the rear side. The third tube portion 93 extends forward

and downward in the storage space S31.

[0078]

As illustrated in Figs. 13 and 14, the third tube portion 93 in the storage

space S31 is led out onto the coupling frame 40 through the front cutout portion

31h. As described above, the third tube portion 93 is disposed in the storage

space S31 from the rear cutout portion 31h to the front cutout portion 31h, so

that the third tube portion 93 can be hidden by the boom 30.

[0079]

Furthermore, the third tube portion 93 is constituted by a metal pipe 93a

at least from the front cutout portion 31h to the rear cutout portion 31h. As a

result, the third tube portion 93 can be prevented from hanging down and being

exposed to the outside.

[0080]

The third tube portion 93 led out onto the coupling frame 40 extends

leftward on the coupling frame 40. The third tube portion 93 is exposed to the

outside of the cover 100 through an opening 101a of a first cover 101 described

later (see Fig. 15).

[0081]

Hereinafter, the configuration of the cover 100 will be described with

reference to Figs. 11 to 13 and 15. The cover 100 is a hollow member that covers

the tube portion 90 and the like. As illustrated in Fig. 15, the cover 100 includes

the first cover 101, a second cover 102, and a third cover 103.

[0082]

The first cover 101 covers the tube portion 90 on the coupling frame 40.

The first cover 101 is formed in a longitudinal shape along the axial direction of

the coupling frame 40. The first cover 101 is formed in a substantially inverted

U shape with an opening facing downward in a cross-sectional view of a side

surface (longitudinal direction). The first cover 101 is provided on an upper

portion of the coupling frame 40. The first cover 101 includes the opening 101a.

[0083]

The opening 101a is a portion through which the third tube portion 93

can be inserted. The opening 101a is formed on the front surface of the first

cover 101. The opening 101a is covered with a stay 101b having a plate surface facing substantially the front-rear direction. The third tube portion 93 is provided so as to penetrate the stay 101b in the front-rear direction. In this way, the third tube portion 93 is exposed from the first cover 101.

[0084]

As described above, in the present embodiment, all the branch portions

91a and 92a are disposed to be shifted from each other in the left-right direction.

As a result, a height of the first cover 101 covering the branch portions 91a and

92a and the like can be reduced, and the cover 100 can be downsized.

[0085]

The second cover 102 covers the fourth opening 31g and the like. The

second cover 102 is formed in a substantially box shape with a right portion

opened. The second cover 102 is formed in a vertically long shape having a

height higher than that of the first cover 101. As illustrated in Fig. 11(a), the

second cover 102 includes a first cutout portion 102a and a second cutout portion

102b.

[0086]

The first cutout portion 102a is formed on the upper surface of the second

cover 102. The first cutout portion 102a is appropriately formed so as not to

interfere with the second tube portion 92. The second cutout portion 102b is

formed on the rear surface of the second cover 102. As illustrated in Figs. 12

and 13, the second cutout portion 102b is appropriately formed so as not to

interfere with the first tube portion 91 and the third tube portion 93.

[0087]

The second cover 102 configured as described above is provided between

the right boom frame 31 and the first cover 101. The fourth opening 31g and the tube portion 90 in the vicinity of the fourth opening 31g are covered with the second cover 102. Furthermore, the second tube portion 92 branched by the branch portion 92a is led out to the outside of the cover 100 through the first cutout portion 102a (see Fig. 11(b)). Furthermore, the first tube portion 91 branched by the branch portion 91a is introduced into the storage space S31 from the cover 100 through the second cutout portion 102b and the front cutout portion 31h. Furthermore, the third tube portion 93 is introduced into the cover

100 from the storage space S31 through the second cutout portion 102b and the

front cutout portion 31h.

[0088]

The third cover 103 illustrated in Fig. 15(a) covers the first tube portion

91 and the second tube portion 92. The third cover 103 is formed in a

substantially bilaterally symmetrical shape with the second cover 102. The

third cover 103 includes a first cutout portion 103a and a second cutout portion

103b formed substantially in the same manner as the second cover 102 (see Fig.

11). The third cover 103 is provided between the left boom frame 31 and the

first cover 101. The third cover 103 covers the first tube portion 91 and the

second tube portion 92 extending from the branch portions 91a and 92a toward

the left boom frame 31. Furthermore, the first tube portion 91 and the second

tube portion 92 branched by the branch portion 92a are led out to the outside of

the cover 100 through the first cutout portion 103a and the second cutout portion

103b.

[0089]

As described above, the front loader 10 according to the present

embodiment includes the boom 30, and the side frame 20 that rockably supports the boom 30 and is provided with the first opening 23 through which the tube portion 90 (the first tube portion 91 and the second tube portion 92 in the present embodiment) for forming a flow path of hydraulic oil can be inserted.

[0090]

With such a configuration, since the tube portion 90 can be disposed in

the side frame 20, it is possible to suppress the tube portion 90 from blocking the

field of view of the operator. Thus, the visibility can be improved.

Furthermore, the tube portion 90 can be hidden by the side frame 20, and the

aesthetic appearance can be improved.

[0091]

Furthermore, the first opening 23 is formed on one side surface (left side

surface in the present embodiment) of the side frame 20 in the left-right direction

(see Fig. 7).

[0092]

With such a configuration, the tube portion 90 can be introduced into the

side frame 20 from the left and right outer sides of the side frame 20.

[0093]

Furthermore, the second opening 24 through which the tube portion 90

can be inserted is formed on a surface of the side frame 20 facing the boom 30

(see Fig. 8).

[0094]

With such a configuration, the tube portion 90 can be led out from the

inside of the side frame 20 toward the boom 30.

[0095]

Furthermore, in the boom 30, the third opening 31d formed on a surface facing the side frame 20 and through which the tube portion 90 can be inserted, and the fourth opening 31g different from the third opening 31d are formed.

[0096]

With such a configuration, it is possible to effectively suppress the tube

portion 90 from blocking the field of view of the operator, and to effectively

improve the visibility.

[0097]

Furthermore, the front loader 10 further includes the coupling frame 40

that couples the left and right booms 30, and the tube portion 90 that is led out

from the inside of the boom 30 onto the coupling frame 40 through the fourth

opening 31g, is branched on the coupling frame 40, and is connected to the left

and right boom cylinders 70 and the left and right bucket cylinders 80 (see Figs.

4 and 5).

[0098]

With such a configuration, the branch portions 91a and 92a of the tube

portion 90 can be gathered on the coupling frame 40. This facilitates assembly

and maintenance of the tube portion 90.

[0099]

Furthermore, the front loader 10 further includes the first cover 101 that

covers the tube portion 90 on the coupling frame 40.

[0100]

With such a configuration, the tube portion 90 on the coupling frame 40

can be hidden by the first cover 101, and the aesthetic appearance can be

improved.

[0101]

Furthermore, the opening 101a is formed in the first cover 101 (see Fig.

).

[0102]

With this configuration, the hydraulic pressure can be used through the

opening 101a.

[0103]

Furthermore, the front loader 10 further includes the second cover 102

that covers the fourth opening 31g.

[0104]

With such a configuration, the fourth opening 31g and the tube portion 90

led out from the fourth opening 31g can be hidden by the second cover 102, and

the aesthetic appearance can be improved.

[0105]

Furthermore, the attitude maintenance mechanism 110 that maintains

an attitude of the bucket 50 (working tool) coupled to the boom 30 by operating

according to rocking of the boom 30 can be attached to the boom 30, and the boom

includes the boss portion 32 (attachment portion) at least a part of which is

disposed inside the boom 30 and to which the attitude maintenance mechanism

110 is attached, and the guide portion 33 at least a part of which is disposed

inside the boom 30 and that guides the tube portion 90 so as to avoid the boss

portion 32.

[0106]

With such a configuration, the tube portion 90 can be easily disposed in

the boom 30.

[0107]

Note that the bucket 50 according to the present embodiment is an

embodiment of a working tool according to the present invention.

Furthermore, the boss portion 32 according to the present embodiment is

an embodiment of an attachment portion according to the present invention.

[0108]

Although the embodiment of the present invention has been described

above, the present invention is not limited to the above configurations, and

various modifications can be made within the scope of the invention described in

the claims.

[0109]

For example, although the first opening 23 is formed on the left side

surface of the side frame 20, a portion where the first opening 23 is formed is not

particularly limited, and can be arbitrarily changed. For example, the first

opening 23 may be formed on the bottom surface of the right side frame 20 or the

right side surface portion 21. Furthermore, the first opening 23 may be formed

in the left side frame 20 instead of the right side frame 20.

[0110]

Furthermore, although the second opening 24 is formed in the upper

portion of the connection portion 22 of the side frame 20, a portion where the

second opening 24 is formed is not particularly limited, and can be arbitrarily

changed. For example, the second opening 24 may be formed at a portion other

than the upper portion of the connection portion 22.

[0111]

Furthermore, the third opening 31d is formed in the bottom surface 31c of

the boom frame 31, but a portion where the third opening 31d is formed is not particularly limited, and can be arbitrarily changed.

[0112]

Furthermore, the fourth opening 31g is formed on the left side surface of

the boom frame 31, but a portion where the fourth opening 31g is formed is not

particularly limited, and can be arbitrarily changed.

[0113]

Furthermore, although the opening 101a of the first cover 101 is formed

on the front side surface of the first cover 101, a portion where the opening 101a

is formed is not particularly limited, and can be arbitrarily changed.

[0114]

Furthermore, although both left and right end portions of the boss portion

32 protrude from the boom 30, this is an example, and at least a part thereof may

be disposed in the boom 30.

[0115]

Furthermore, although the substantially entire guide portion 33 is

disposed in the boom 30, this is merely an example, and at least a part thereof

may be disposed in the boom 30.

[0116]

Furthermore, although the first tube portion 91 and the second tube

portion 92 are provided so as to pass above the boss portion 32, this is an

example, and a portion where the first tube portion 91 and the like pass through

the boss portion 32 is not particularly limited. For example, the first tube

portion 91 and the like may be provided so as to pass below the boss portion 32.

In this case, the guide portion 33 may be provided, for example, from the boss

portion 32 to the upper surface 31a of the boom frame 31 so as to guide the first tube portion 91 and the like below the boss portion 32.

[0117]

Furthermore, although the tube portion 90 includes the third tube portion

93, this is an example, and in a case where a hydraulic device such as a snow

blower is not provided, the third tube portion 93 may not be installed.

[0118]

Furthermore, although the front loader 10 includes the attitude

maintenance mechanism 110, this is an example, and the present invention is

also applicable to a front loader not including the attitude maintenance

mechanism 110.

INDUSTRIAL APPLICABILITY

[0119]

The present invention can be used for a technique of a front loader in

which a working tool coupled to a boom can be operated by hydraulic oil.

REFERENCE SIGNS LIST

[0120]

10: Front loader

20: Side frame

23: First opening

30: Boom

90: Tube portion

Claims (9)

1. A front loader comprising:

a boom; and

a side frame rockably supporting the boom and formed with a first

opening through which a tube portion forming a flow path for hydraulic oil can be

inserted.

2. The front loader according to claim 1, wherein

the first opening is formed on one side surface of the side frame in a left

right direction.

3. The front loader according to claim 2, wherein

a second opening through which the tube portion can be inserted is

formed on a surface of the side frame facing the boom.

4. The front loader according to any one of claims 1 to 3, wherein

the boom is formed with:

a third opening that is formed on a surface facing the side frame

and through which the tube portion can be inserted; and

a fourth opening different from the third opening.

5. The front loader according to claim 4, further comprising a coupling frame

that couples the boom on a right side and the boom on a left side,

wherein the tube portion is led out from an inside of the boom to the

coupling frame through the fourth opening, branched on the coupling frame, and

connected to left and right boom cylinders and left and right bucket cylinders.

6. The front loader according to claim 5, further comprising a first cover that

covers the tube portion on the coupling frame.

7. The front loader according to claim 6, wherein an opening is formed in the first cover.

8. The front loader according to any one of claims 5 to 7, further comprising

a second cover that covers the fourth opening.

9. The front loader according to any one of claims 4 to 8, wherein

an attitude maintenance mechanism can be attached to the boom, the

attitude maintenance mechanism being configured to maintain an attitude of a

working tool coupled to the boom by operating in accordance with rocking of the

boom,and

the boom includes:

an attachment portion at least a part of which is disposed inside

the boom and that attaches the attitude maintenance mechanism; and

a guide portion at least a part of which is disposed inside the boom

and that guides the tube portion so as to avoid the attachment portion.