JP3353753B2 - Side frame structure and body frame for industrial vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a side frame structure and a body frame constituting side portions of a body frame of an industrial vehicle such as a forklift.

[0002]

2. Description of the Related Art Conventionally, a body frame of a forklift employs a side frame structure in which a pair of left and right box-shaped structures for reinforcement are provided inside side plates forming left and right side surfaces. Since a box-shaped structure portion exists on the left and right, a large accommodation space in the vehicle width direction cannot be secured inside the vehicle body frame. Therefore, in the case of a battery-type forklift, the battery is usually arranged above the rear wheel. For this reason, the driver's seat (seated position) is higher than that of an engine vehicle, the center of gravity of the machine is higher, and pitching (swaying back and forth) is worse. There was a problem that was disadvantageous.

In order to lower the position of the battery, it is necessary to abolish the box-shaped structure of the side frame and adopt an arrangement in which the battery is dropped between the front wheel and the rear wheel. Another problem arises in that the strength of the frame is reduced at the side frame portions.

Japanese Unexamined Patent Publication No. 9-77487 discloses that the box-shaped structure of the side frame is abolished, the space between the front wheel and the rear wheel is widened in the width direction, and the battery is dropped between the front wheel and the rear wheel. Disclosed is a forklift body frame structure that is arranged. According to this publication, as shown in FIG. 15, the side frame 90 includes a side panel 92 joined so as to extend upward from a side surface of the bottom plate 91,
Left and right side panel reinforcing members 93 projecting upward from the upper surface of the side panel 92 and located inside the upper portion of the side panel 92 are provided. The side panel reinforcing member 93 was connected to a front plate and a rear plate (both not shown) constituting a front frame portion and a rear frame portion, respectively. The battery 94 was housed inside the side panel reinforcing member 93.

In this publication, a side frame structure shown in FIG. 16 is cited as a prior art. The side frame 90 is formed by bending an upper portion of a side panel 95 extending upward from an upper end portion of the bottom plate 91 inward to form an upper bent portion 95a, and a reinforcing member 96 having an L-shaped cross section inside the upper bent portion 95a. Is formed to form a cylindrical structure portion 97 whose cross section is closed in an annular shape, and the cylindrical structure portion 97 has been reinforced.

[0006]

By the way, the battery replacement work is carried out by lifting the battery. However, if the side frame has a height width, the lifting amount at the time of the battery replacement work is increased and the workability is deteriorated. . Therefore, FIG.
As shown in FIG. 7, there is a demand to reduce the height (H1) of the side frame 90 to reduce the amount of lifting of the battery.

On the other hand, in order to reinforce the vehicle body frame, it is necessary to increase the joining distance between the front and rear ends of the side frame. Therefore, as shown in FIG. 17, the height H2 at the front and rear ends of the side frame 90 is made as long as possible. I want to do (H2> H
There is a request 1).

The conventional side frame 90 shown in FIG. 15 and FIG. 16 has a thick side panel reinforcing member 93 and a tubular structure 97 at the upper end, so that the upper end line shape of the side frame 90 is bent. Forming into a shape is difficult to manufacture or leads to a complicated manufacturing method. In order to respond to the above two requirements by using the conventional side frame 90, for example, as shown in FIG. 17, the height width H1 of the conventional side frame 90 is reduced, and the rib 98 is joined to the front and rear ends thereof. A frame structure is conceivable. However, there is a problem that it is difficult to obtain a sufficient reinforcing effect because the structure is such that stress is concentrated at a joint (joint) of the rib 98. For this reason, the upper end line shape of the side frame is easily formed into a desired shape, for example, a line shape that is recessed downward at a central portion corresponding to the battery chamber, and the degree of freedom in selecting the shape is high. A side frame structure is desired.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a thin side frame so as to secure a wide accommodation room in the vehicle width direction between a front wheel and a rear wheel with a high reinforcing effect of a body frame. In addition, the height of the side frame can be shortened at the location corresponding to the storage room. It is an object of the present invention to provide a side frame structure and a body frame of an industrial vehicle which can be realized.

[0010]

In order to achieve the above object, an invention according to a first aspect of the present invention is directed to a front frame portion standing up and down before and after a bottom frame portion constituting a bottom portion of a body frame of an industrial vehicle. A side frame structure of an industrial vehicle that connects between a rear frame portion and left and right side portions of the vehicle body and connects the rear frame portion so as to partition an accommodation room therein,
One or more plate members, the front and rear end portions of which are directly connected to the front frame portion and the rear frame portion, and a plate member that determines an upper end line shape of a side frame among the plate members is extended at least partially upward, It said provided at least one integrally of sheet material, possess a pipe structure portion extending seamlessly across between the front frame portion and the rear frame part, an upper end line of the side frame
The plate that determines the shape extends above the pipe structure
In the front-rear direction corresponding to the storage chamber
Place to have a recessed downward by the recess.

[0011]

According to a second aspect of the present invention, in the first aspect of the present invention, there are provided a plurality of the plate members, and at least two plate members are arranged one above the other so as to partially overlap one another vertically. A plurality of plate members including the upper and lower two plate members are joined at the joint portion so as to form the pipe structure.

[0013] The invention described in claim 3 is the invention according to claim 2, wherein the pipe structure by bending end portions of the two plate members are joined by some overlapping state vertically formed Have been.

According to a fourth aspect of the present invention, in the second aspect , at least one of the plurality of plate members forming the pipe structure is a thin plate member, and only the one thin plate member is provided. A bent portion for forming the pipe structure is formed at the other end, and the other plate members except the one thin plate member are two flat plate members, and one of the two flat plate members is thick. The pipe structure is formed by joining the thin plate material between the thin plate material and the flat plate material. The invention according to claim 5 is a vehicle body frame for an industrial vehicle.
Standing before and after the bottom frame that constitutes the bottom of the
Between the front and rear frames
The left and right sides are formed and a compartment is defined inside.
Industrial vehicle side frame structure
To the front frame and the rear frame.
One or more plate members directly connected to the rear end, and among the plate members
Reduce the number of plates that determine the top line shape of the side frame
With some of the plate materials extended
Both are provided integrally with one piece, and the front frame part and
Seamlessly extended between the rear frame parts
A pipe structure, and there are a plurality of said plate members,
Both of the two plates are placed vertically and partly vertically
Are joined together so as to form a plurality
A plurality of plate members including the lower two plate members form the pipe structure.
Before forming the pipe structure
At least one of the plurality of plate members is a thin plate member,
For forming the pipe structure only in one sheet material
Other plate material except the one thin plate material in which the bent portion is formed
Is two flat plates, and one of the two flat plates has a thickness
Meat, wherein the thick material is provided between the thin plate material and the flat plate material.
The pipe structure is formed by joining the flat plate material
Have been.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the inside of the pipe structure is filled with a filler. The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the plate and the pipe structure have a rear extension that extends rearward from a front surface of the rear frame. And the rear extension is joined to a rear wheel support frame that supports the rear wheel.

According to an eighth aspect of the present invention, there is provided a vehicle body frame for an industrial vehicle, wherein a bottom frame portion constituting a bottom portion of the vehicle body frame of the industrial vehicle, and a front frame portion and a rear frame erected before and after the bottom frame portion. The side according to any one of claims 1 to 7, wherein a frame portion and the front frame portion and the rear frame portion are connected to each other so as to form left and right side portions of the vehicle body and to define a housing chamber therein. And a side frame having a frame structure. According to the first aspect of the present invention, when an input load (load) is transmitted between the front frame portion and the rear frame portion, a stress such as a seam is applied to the plate material in the direction in which the force is transmitted. Since there is no place to concentrate, strength is secured. Also,
Since there is no stress concentration point such as a joint in the middle of a force transmission path in the pipe structure, strength and rigidity are secured by the pipe structure. In addition, since the plate material that determines the upper end line shape of the side frame extends at least partially above the pipe structure, only the cutting of the plate material for processing the upwardly extending portion of the plate material into a desired shape is performed. Since the upper end line shape of the frame can be freely set, the degree of freedom in selecting the upper end line shape is increased without complicating the manufacturing process so much. For example, by processing a portion of this plate material extending upward from the pipe structure portion into a concave shape at a portion corresponding to the storage chamber,
It is possible to shorten the height and width of the side frame at a location corresponding to the storage chamber while securing the necessary joining length at the front and rear ends of the side frame. Also, the side frame
The plate material that determines the top line shape of the pipe is above the pipe structure
In the front-rear direction corresponding to the accommodation room in the part extending toward
Since the central part is recessed downward, the side frame
While maintaining the joint distance between the front and rear ends,
The height and width at the location corresponding to the accommodation room of the first embodiment are reduced. This
Therefore, for example, accommodation of a battery etc. accommodated in the accommodation room
Reduce the amount of lifting of items when removing items
And become possible.

[0017]

According to the invention of claim 2 , according to claim 1,
In addition to the operation of the invention described in the above, utilizing the joint portion that is joined so as to partially overlap the top and bottom of two plate materials arranged vertically among a plurality of plate materials constituting the side frame,
A pipe structure is formed at a joint portion of a plurality of plate members including the upper and lower two plate members. Without using pipe material,
Strength and rigidity are increased by devising the joining structure of the plate materials.

According to the invention of claim 3 , according to claim 2,
In addition to the operation of the invention described in (1), by joining the bent ends of the two plate members so as to partially overlap vertically, a pipe structure is formed at the joint. Therefore, the pipe structure is formed by a small number of plate members such as two. For example, since the number of plate members is small, the assembling work of the side frame is simplified.

According to the invention described in claim 4 , according to claim 2,
In addition to the effect of the invention described in (1), a pipe structure is formed by sandwiching a thick flat plate material at the joint between the thin plate material and the flat plate material. For this reason, the vertical direction (height direction) of thick flat plate material
By adjusting the length, the strength can be easily manipulated, so that the strength can be easily designed. In addition, it is only necessary to perform the bending process for the bent portion on only one thin plate material, and it is possible to reduce the labor of the processing such as the bending process.

According to the invention of claim 6, according to claim 1,
In addition to the functions of the invention described in any one of the above-described embodiments, since the inside of the pipe structure is filled with the filler, the strength and rigidity of the side frame are further increased.

According to the invention of claim 7, according to claim 1,
In addition to the functions of the invention described in any one of the above-described embodiments, the plate member and the pipe structure portion extend rearward from the front surface of the rear frame portion, and the rear extension portion is joined to the rear wheel support frame portion. Also, strength and rigidity are secured even with respect to an input load transmitted from the rear wheel to the plate and the pipe structure via the support frame.

According to the eighth aspect of the present invention, the side frame having the side frame structure according to any one of the first to seventh aspects is adopted in the vehicle body frame, so that the distance between the front wheel and the rear wheel is increased. A large accommodation room is secured in the vehicle width direction. For example, it is possible to arrange an object such as a battery to be dropped between the front wheel and the rear wheel.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 6, the battery type forklift 1 as an industrial vehicle is a front-balanced four-wheeled vehicle with front-wheel drive and rear-wheel steering. A mast 3 is provided at the front of the vehicle body 2 via a tilt cylinder 4 so as to be tiltable back and forth. The mast 3 slides and expands and contracts when the hydraulic lift cylinder 5 erected behind it is driven, and the fork 6 moves up and down along the mast 3. The battery 7 has a front wheel 8 inside the vehicle body 2.
It is housed in a battery chamber 10 provided between the rear wheel 9. A hood 12 having a seat 11 on its upper surface is provided to be openable and closable about its rear end. The toe board 13 is provided so as to be openable and closable about the front end. The battery 7 is replaced while the hood 12 and the toeboard 13 are both opened and the side cover 14 is removed.

FIG. 4 is a perspective view showing a main part of the vehicle body frame F. As shown in the figure, the front frame section 20 and the rear frame section 30 are provided upright before and after the bottom frame section 40. Side frames 50 are connected between the front frame portion 20 and the rear frame portion 30 so as to cover both left and right sides of the vehicle body. The battery compartment 10 includes left and right side frames 50 and 50 and front and rear frame portions 2.
0 and 30 are formed inside the body frame F so as to be surrounded on all sides.

The front frame section 20 includes a front axle plate 21 and front cross plates 22 and 2.
3, 24, a mud guard 25, a support plate 26, and the like. Each of the members 21, 25, 26 is provided as a pair of left and right.

The left and right front axle plates 21
Three front cross plates 22, 23, 23, which are arranged at predetermined intervals in the vehicle width direction and extend horizontally in the vehicle width direction.
24 are connected and fixed to each other. The left and right mudguards 25 are welded to the outer surfaces of the left and right front axle plates 21, respectively. Each mudguard 25
A support plate 26 is welded to an upper surface of the front axle plate 21 so as to protrude in parallel with an upper end portion of the front axle plate 21.
Thus, a pair of left and right tilt cylinder support portions (support brackets) 27 for connecting and supporting the base portions of the left and right tilt cylinders 4 are configured. A connection hole 25a for connecting the left and right front pillars 15 (shown in FIG. 6) is formed in the mudguard 25.

The rear frame portion 30 includes left and right outer rear stand plates 31 erected from the bottom frame portion 40.
And left and right inner rear stand plates 32, left and right rear upper plates 33, rear axle plates 34, and the like, which cover the left and right upper portions and are bent downward so as to be concave at the center in the vehicle width direction. The rear axle plates 34 are welded to the lower surfaces of the lower bent portions of the left and right rear upper plates 33, and the front portions thereof are welded to the rear surfaces of the left and right rear stand plates 32. Left and right outer rear stand plates 3
1 has a lower part standing substantially vertically so as to form a rear surface of the battery chamber 10, and an upper part thereof is bent obliquely rearward and is welded to the lower surfaces of the left and right rear upper plates 33. A pair of front and rear rear axle brackets (not shown) for swingably supporting a rear axle beam (not shown) for supporting left and right rear wheels (steering wheels) 9 are provided on the lower surface of the rear axle plate 34. Has been fixed. That is, the rear frame portion 30 forms a rear wheel support frame portion that supports the rear wheel 9. Left and right rear pillars 16 (FIG. 6)
Are mounted on support frames (not shown) mounted on the upper surfaces of the left and right rear upper plates 33.

The side frame 50 is composed of two upper and lower plate members, an upper side plate 51 and a lower side plate 52. The upper side plate 51 and the lower side plate 52 are joined so as to partially overlap vertically. The upper side plate 51 is made of a plate material which is cut so as to have a concave portion 50a at an upper edge portion corresponding to the battery chamber 10, and a pair of front and rear portions extending obliquely upward and forward at both front and rear ends of the concave portion 50a. Ribs 51a, 5
1b is formed. The lower side plate 52 is bent and formed in a substantially L-shaped cross section having a side plate portion 52a and a bottom plate portion 52b, and the bottom plate portions 52b of the left and right lower side plates 52 are respectively provided at left and right ends of a square plate-shaped bottom plate 41. Welded.

A mud guard 25 is supported by welding on a front end of a bottom plate 52b of the lower side plate 52 via a base plate 42. The bottom frame portion 40 includes a bottom plate 41 and a base plate 42.

The front end of the side frame 50 is curved so as to be in close contact with the rear surface of the mud guard 25, and the rear end extends rearward from the front surface of the rear stand plate 31. The front end surface of the side frame 50 is welded to the rear surface of the mudguard 25 in a close contact state, and the inner surface of the rear end of the side frame 50 is welded to the outer surfaces of the rear stand plate 31 and the rear upper plate 33. That is, a rearwardly extending portion extending rearward from the front surface of the rear frame portion 30 of the side frame 50 is welded to the side surface of the rear wheel support frame 30.

The battery compartment 10 has a front frame 2
0, the front surface of the rear frame portion 30, and the left and right side frames 50 are formed in a rectangular box shape surrounded on all sides. Since the left and right side frames 50 have a plate-like structure, they are thinner in the vehicle width direction than the conventional box-type structure, and have a sufficient vehicle width between the front wheels 8 and the rear wheels 9 to accommodate the battery 7. Wide accommodation space is secured in the direction.

Next, the structure of the side frame 50 is shown in FIGS.
This will be described in detail with reference to FIG. FIG. 3 is a front sectional view taken along the line A in FIG. At the lower end of the upper side plate 51, a bent portion 51c that bends obliquely downward to the outside and then bends at an angle that returns to a direction parallel to the original is formed over the entire region in the front-rear direction. On the other hand, the lower side plate 5
A bent portion 52c is formed at the upper end portion of the second plate 2 and is bent inward in substantially the same bent shape as the lower end portion of the upper side plate 51.

That is, the bent portion 51c provided at the lower end of the upper side plate 51 extends in parallel to the main surface direction with a slope portion 51d which is bent obliquely outward and downward with respect to the main surface direction of the upper side plate 51. And a support plate 51e. Also, the lower side plate 52
The bent portion 52c provided at the upper end portion of the lower side plate 52 has a slope portion 52d bent obliquely upward and inward with respect to the main surface direction of the lower side plate 52, and a support plate portion 52e extending parallel to the main surface direction. Then, in a state where the upper side plate 51 and the lower side plate 52 are partially overlapped vertically, the support plate portions 51e, 52e are welded to the side surface of the base end portion only a predetermined distance from the bending portions 51c, 52c on the other side. Are joined together. Due to the joining of the bent portions 51c, 52c of both the upper side plate 51 and the lower side plate 52, the side frame 50 has a pipe structure portion 5 having a hollow portion having a rhombic cross section.
0b extends over the entire area in the front-rear direction.

As shown in FIG. 1, FIG. 4, etc., the upper side plate 51 which defines the upper end line shape of the side frame 50 is a single plate positioned so as to extend upward from the pipe structure 50b. Since it is easy to form a desired shape by cutting or the like, the degree of freedom in selecting the upper end line shape of the side frame 50 is increased. The upper side plate 51 has a concave portion 50a formed by processing a central portion in the front-rear direction corresponding to the battery chamber 10 into a concave shape in a portion located above the pipe structure portion 50b.
And a pair of front and rear rib portions 51a and 51b are formed. Thereby, the side frame 50 has a concave portion 50a that curves downward in the center region of the upper end line, and a pair of front and rear rib portions 51a and 51b that extend obliquely upward in the front and rear directions. That is, the side frame 50
The joining distance of the front and rear end portions of the pair of front and rear rib portions 51a, 51
b, the height and width of the portion corresponding to the battery chamber 10 are shortened due to the presence of the concave portion 50a.

The replacement of the battery 7 is performed by removing the side cover 14 (shown in FIG. 6) disposed above the side frame 50. Since the height of the side frame 50 at the location corresponding to the battery chamber 10 is reduced, the lifting amount of the battery 7 at the time of battery replacement work can be reduced.

As shown in FIG. 5, the battery compartment 10 is formed sufficiently wide in the vehicle width direction. The battery 7 is arranged, for example, in the battery chamber 10 to one side in the vehicle width direction (hatched portion in the figure) as shown in FIG. Space 1 not used for housing battery 7 in battery compartment 10
Reference numeral 0a is used for storing an oil tank, electric components and the like. Since the battery compartment 10 does not have a member corresponding to a partition for partitioning the compartment, the degree of freedom in the layout of the battery 7, the housing components, and the like in the battery compartment 10 is increased. For this reason, it is possible to improve the storage efficiency of the battery chamber 10 by devising the layout of the storage components,
Even if the battery compartment 10 is not extended in the front-back direction, the battery compartment 1
Since all the parts to be housed in 0 can be arranged,
Although the battery 7 is disposed between the front wheel 8 and the rear wheel 9, the forklift 1 has a relatively short wheelbase for the arrangement.

Next, the operation of the vehicle body frame structure configured as described above will be described. Since the two side plates 51 and 52 constituting the side frame 50 are formed of a single plate having front and rear ends directly connected to the front frame portion 20 and the rear frame portion 30, stress is concentrated in the front and rear direction of the side frame 50. There are no seams that cause The input load input from the tilt cylinder support portion 27 due to the load or the like is applied to each of the side plates 51 and 52 formed of a single plate.
In the front-rear direction and exits to the rear frame portion 30. At this time, even though the side plates 51 and 52 may bend, no stress concentration portion is generated on the way. In addition, the strength and rigidity of the side frame 50 are increased by the pipe structure 50b extending seamlessly in the front-rear direction at the joint between the side plates 51 and 52.
A strong side frame structure results.

Also, when the load from the rear wheel 9 is transmitted to the side frame 50 via the rear frame portion 30,
The input load from the rear wheel 9 is transmitted through one of the side plates 51 and 52 constituting the side frame 50 without a stress concentration portion such as a seam in the middle thereof, and the strength of the side frame 50 due to the presence of the pipe structure 50b. In addition, since the rigidity is increased, the strength is secured against an input load from the rear wheel 9.

Further, at the time of replacing the battery 7, the height of the portion corresponding to the battery chamber 10 of the side frame 50 is shortened by the presence of the concave portion 50a, so that the lifting amount at the time of replacing the battery 7 can be reduced. Therefore, the workability of replacing the battery 7 is improved.

Therefore, in this embodiment, the following effects can be obtained. (1) A side frame structure in which two side plates 51 and 52 each formed of a single plate with no seam in the front-rear direction are vertically overlapped and partially joined, and a pipe structure 50b is extended at the joint. Therefore, the side frame 50 can be made thin while ensuring the necessary strength, and the battery chamber 10 that is sufficiently wide in the vehicle width direction can be defined inside the body frame F. Therefore, it is possible to adopt an arrangement in which the battery 7 is dropped between the front wheel 8 and the rear wheel 9, and the seat 11
Can be set as low as an engine type forklift. Also, since the machine center of gravity can be lowered,
Problems such as pitching are alleviated. Further, since the seat 11 is low, the head guard 17 can be arranged low, which is effective for indoor work with a low ceiling.

(2) Since the upper side plate 51 that determines the shape of the upper end line of the side frame 50 has a plate shape that can be easily processed by cutting or the like, the upper end line of the side frame 50 can be formed without complicating the manufacture of the side frame 50. The degree of freedom in selecting a shape can be increased. For example, the side plate 51 can be easily processed into a shape having rib portions 51a and 51b at front and rear ends. In addition, the side plate 51 can be easily formed into a shape having a concave portion 50a that is curved downward at the center in the front-rear direction in order to reduce the height and width of a portion corresponding to the battery chamber 10 of the side frame 50. Therefore, the joining distance of the front and rear end portions of the side frame 50 to the front and rear frame portions 20 and 30 is set to
1a and 51b can be secured longer to ensure a high joining strength of the connecting portion, and the presence of the concave portion 50a reduces the height and width of a portion corresponding to the battery chamber 10 of the side frame 50, thereby enabling battery replacement work. The lifting amount of the battery 7 can be reduced.

(3) Bent portions 51c and 52c are formed at the joining end of the two side plates 51 and 52, and the bent portion 51 is formed at the joining portion of the two side plates 51 and 52.
Since the pipe structure 50b is formed by c and 52c, the pipe structure 50b can be formed by a small number of plate members, such as two. Further, members other than the side plates 51 and 52 are not required to form the pipe structure 50b.

(4) Since the battery compartment 10 which is wide in the vehicle width direction and has no members such as partitions is secured, the degree of freedom in the layout of the housing components including the battery 7 in the battery compartment 10 is increased. By improving the storage efficiency by devising the layout of the storage components, the front-rear dimension of the battery chamber 10 can be reduced, and the forklift 1 having a relatively short wheelbase can be provided.

(Second Embodiment) Next, a second embodiment will be described. In this embodiment, a pipe structure is formed by using three plate members constituting a side frame.

As shown in FIGS. 7 and 8, the structure of the side frame 50 is a flat, thin upper side plate 5.
3, a lower side plate 52 having an L-shaped cross section, and a thick side cross plate 54 having a flat plate shape. The lower side plate 52 is a plate material serving as a design surface appearing on the outside, and a relatively thin thin plate material is used. The bent portion 52c of the lower side plate 52 is welded to the outer surface of the upper side plate 53, and the three members are welded in a state where the thick side cross plate 54 is sandwiched between the upper side plate 53 and the lower side plate 52. I have. As a result, the three plates 52, 5
Pipe structure 50c closed cylindrically by 3, 54
Is formed. The pipe structure portion 50c extends around the side frame 50, and the side frame 50 has a substantially uniform cross-sectional structure.

The upper side frame 53 has the same shape as the upper side plate in the first embodiment except that the lower end portion is formed in a flat plate shape extending straight. It has a pair of rib portions 53a, 53b.

In this side frame structure, the length in the vertical direction (height direction) of the thick side cross plate 54 is a factor that determines the rigidity of the side frame 50.
The rigidity can be easily controlled by adjusting the length of the side cross plate 54 in the vertical direction. Therefore, the strength can be easily designed by adjusting the length of the side cross plate 54 in the vertical direction.

Further, since the upper side plate 53 extending upward from the pipe structure portion 50c and defining the upper end line shape of the side frame 50 is plate-shaped, the shape can be easily processed. Therefore, even if the upper end line shape of the side frame 50 is designed to have the concave portion 50a curved downward at the center portion in the front-rear direction and the pair of front and rear rib portions 53a and 53b, the upper side plate 53 is formed by machining such as cutting. Therefore, the manufacture of the side frame 50 can be simplified.

Further, the point that the rear extension portion extending rearward from the front surface of the rear stand plate 31 of the side frame 50 is joined to the outer side surface of the rear frame portion 30 is the same as in the first embodiment.

According to this embodiment, the effects (1), (2) and (4) described in the first embodiment can be obtained similarly. That is, (1) the thickness of the side frame 50 can be reduced while securing the strength and rigidity, and the battery chamber 10 that is wide in the vehicle width direction can be widely secured. (2) The side frame 50 can be relatively easily manufactured into a shape having the concave portion 50a and the rib portions 53a and 53b, and the amount of lifting of the battery 7 can be reduced while securing the joining strength of the front and rear end portions of the side frame 50. Can be. (4) The forklift 1 having a relatively short wheelbase can be provided.

In addition, the following effects can be obtained. (5) Since the pipe structure 50c is formed by joining the thick side cross plate 54 between the lower side plate 52 and the upper side plate 53, the longitudinal length of the side cross plate 54 is adjusted. In addition, the strength of the side frame 50 can be easily designed. For example, if there is a seam, strength design must be performed in consideration of stress concentration at the seam, etc., and calculation becomes complicated, making strength design difficult. It will be easier.

(6) Since only one of the three plates 52, 53, and 54 forming the pipe structure 50c needs to be bent, the bending work is reduced. Further, since the plate material to be bent is the lower side plate 52 serving as the design surface, the bent portion for the pipe structure 50c can be formed together with the bending process for the design, and the processing of the bending can be performed from this point as well. It does not take time and effort. Furthermore, since the plate used for the design surface is a thin plate,
Easy to bend.

(Third Embodiment) Next, a third embodiment will be described. This embodiment is an example in which a filler is filled inside a pipe structure.

FIG. 9 shows a pipe structure 50 formed at the joint between the upper side plate 51 and the lower side plate 52 in the side frame 50 of the first embodiment.
Filler 60 is filled in the inside of b.

FIG. 10 shows a side frame 50 according to the second embodiment in which a filler 60 is filled in a pipe structure 50c formed at a joint between an upper side plate 53 and a lower side plate 52. ing. FIG.
In both FIGS. 10A and 10B, a foaming resin (for example, urethane foam) is used as the filler 60. The filler 60 fills the entire inside of the pipe structures 50b, 50c.

The filling material 60 is preferably made of a material having a fluidity and a small specific gravity, for example, a resin at the time of filling, in consideration of good filling workability and reduction in the weight of the side frame 50. In addition, it is preferable to use a foaming material in order to reduce the weight. As the resin, a known material other than urethane can be used.

In this embodiment, the following effects can be obtained. (7) Filler 60 is provided inside pipe structure portions 50b and 50c.
, The strength and rigidity of the side frame 50 can be further improved. Further, since the filler 60 is made of a foamed resin (urethane foam), the side frame 50 is light in weight for the structure filled with the filler, and the filling operation is also easy. Further, a vibration absorbing effect can be obtained by the filler 60.

The embodiment is not limited to the above, and may be modified as follows, for example. The configuration in which the pipe structure is formed at the joint between the two side plates is not limited to the above embodiments. FIG.
As shown in FIG. 5, the joint end of each side plate 51, 52 is bent into an L-shaped cross section, and the respective bent end 51
f and 52f are joined so as to form a square tube to form a pipe structure 50b.

As shown in FIG. 12, the joint end 51i of the upper side plate 51 is bent into a substantially U-shaped cross section, and a bent concave portion 51g having a substantially U-shaped cross section is formed on the upper inner surface of the side plate 52a of the lower side plate 52. Are joined to form a pipe structure 50d. The bent recess 51i is a bent recess 51g.
And a support plate 51h. According to this configuration, 2
Pipe structure 50 with only one side plate 51, 52
d can be formed and one side (lower side plate 52)
Since the plate is flat, it is difficult to cause a problem that the dimensional error is duplicated and the dimensional accuracy of the joint is deteriorated, and a strong joint strength is secured.

As shown in FIG. 13, a convex portion 52g for design is formed by bending on the lower side plate 52 to form an uneven design surface, and the back surface of the uneven design portion and the outer surface of the upper side plate 53 are formed. Are joined to form a pipe structure 50e. In this case, since two pipe structures 50e are formed, the strength of the side frame 50 can be further increased by the plurality of pipe structures 50e. Further, the pipe structure 50e can be formed by using the convex portion 52g for design.

The pipe structure is not limited to being formed by a joint between a plurality of side plates. For example, as shown in FIG. 14, a pipe member 56 can be joined to a side surface of a side plate 55 having a side plate portion 55a and a bottom plate portion 55b as plate members to form a pipe structure.
The pipe member 56 is joined to a predetermined height such that the upper end of the side plate 55 extends upward. The upper portion of the side plate 55 has a concave portion 50.
a and a rib portion 55a (the rear rib portion is omitted in the drawing). Also according to this configuration, the joining distance between the front and rear ends of the side frame 50 can be increased, and the height and width of the portion corresponding to the battery chamber 10 can be reduced. As a result, the front and rear joining strength of the side frame 50 can be ensured to be high, and the amount of lifting when replacing the battery 7 can be reduced.

The pipe structures 50b, 50d, 50e, 56 of each side frame 50 shown in FIGS.
May be filled with a filler (for example, foaming resin). By filling the filler, the strength and rigidity of the side frame 50 can be increased, and the body frame F can have a more reinforced structure.

The shape of the upper end line of the side frame 50 is not limited to the shape of each of the above embodiments. For example, a predetermined shape determined by a design surface instead of a shape determined by a functional surface can be applied. The side frame may have a shape that bulges upward at a location corresponding to the battery chamber, for example. Further, a shape in which only one of the front and rear ends of the side frame is extended upward may be used. Regardless of the purpose of determining the shape, adopting this side frame structure increases the degree of freedom in selecting the top line shape of the side frame without increasing the manufacturing burden, so design the shape according to the purpose. It will be easier.

サ イ ド One side frame may have three or more pipe structures. In this case, a plurality of types of pipe structures such as a pipe structure or a pipe material structure formed by joining a plurality of plate materials may be mixed.

The pipe structure may extend obliquely with respect to the horizontal, or may extend slightly curved. ○ It may be applied to an engine type forklift.

The industrial vehicles are not limited to forklifts. That is, a side frame structure may be adopted for an industrial vehicle other than a forklift. For example, it may be employed in a tractor shovel.

The technical ideas other than the claims that can be grasped from the embodiment and other examples are described below. (1) In claim 2 , at least one of the plurality of plate members forming the pipe structure portion has a bent portion for forming the pipe structure portion. In this case, the number of plates required for forming the pipe structure can be reduced.

(2) In claim 2 , at least one of the plurality of plate members forming the pipe structure is a thin plate, and the pipe structure is formed only on the one thin plate. A bent portion is formed. In this case, since a bending process is performed on a thin sheet material having a relatively small thickness, a process for forming a bent portion is easily performed.

(3) In the technical idea of claim 4 or (2), the thin plate material is a plate material which appears on the outer surface of the vehicle and serves as a design surface. In this case, when the plate material to be the design surface is bent and formed for the design, the bent portion for the pipe structure can be formed at the same time, and only one operation is required.

(4) In any one of the sixth aspect and the technical ideas (1) to (3), the filler filled in the pipe structure portion is made of a resin. In this case, the filling operation of the filler is relatively easy, and the side frame is light in weight for the filling amount.

(5) Claims 1 to 7 and (1) to
In any of (4), the accommodation room is a battery room. By arranging the battery so as to be dropped between the front wheel and the rear wheel, the arrangement position can be lowered. Further, when this configuration is applied to the first aspect of the present invention, the amount of lifting of the battery at the time of battery replacement work is small.

(6) The industrial vehicle is a four-wheel counterbalanced industrial vehicle.

[0075]

As described in detail above, according to the first and eighth aspects of the present invention, the side frame is reduced in thickness in the vehicle width direction while ensuring high strength in the side frame due to the presence of the plate member and the pipe structure. The upper part of the side frame can be formed by a relatively simple processing method such as cutting. The freedom of choice can be increased without complicating the manufacturing method. Also, the side frame
Where the plate material that determines the top line shape of the space corresponds to the storage room
Is recessed downward at the junction distance of the front and rear ends of the side frame.
While keeping the separation, only the height and width of the location
Can be shortened. For example, the storage of batteries etc.
When removing items, reduce the lifting amount
Can be.

[0076]

According to the second and eighth aspects of the present invention, in addition to the effects of the first aspect of the present invention, a pipe structure is formed by using a joint portion of a plurality of plate members constituting a side frame. Therefore, the strength and rigidity can be increased only by the plate material without using the pipe material.

[0078] According to the invention described in claim 3 and 8, wherein in addition to the effects of the invention according to claim 2, two of the bent end of the plate is partially overlapped vertically are joined with and pipe structure Is formed, the pipe structure can be formed with a small number of plate members, such as two. Therefore, the number of plate members is small and the assembling work of the side frame is easy.

According to the fourth and eighth aspects of the present invention, in addition to the effects of the second aspect , a pipe structure is provided by sandwiching a thick flat plate at the joint between the thin plate and the flat plate. Since the portion is formed, the strength design can be facilitated by adjusting the length of the thick flat plate in the vertical direction. Further, the bending process for forming the bent portion may be performed only on one thin plate material, and the labor of the processing such as the bending process can be reduced.
According to the invention as set forth in claims 5 and 8, a plate material and a pipe
The strength of the side frame is ensured by the presence of the structure
A storage room with a thin side frame while wide in the vehicle width direction
As well as extending above the pipe structure
Part is a plate material, so the top line shape of the side frame
Can be formed by relatively simple processing methods such as cutting.
The degree of freedom in selecting the top line shape of the
It can be increased without complicating the manufacturing method. Ma
Also, connect the joints of the multiple plates that make up the side frame.
The pipe structure is formed using
Increases strength and rigidity only with plate material without using
Can be Furthermore, the joint between the thin plate and the flat plate
The pipe structure is formed by sandwiching a thick flat plate
By adjusting the length of the thick flat plate in the vertical direction,
Strength design can be facilitated. Also form a bent part
Only need to bend one sheet of material.
Processing time such as processing can be reduced.

According to the invention described in claims 6 and 8, in addition to the effect of the invention described in any one of claims 1 to 5,
Since the filler is filled inside the pipe structure, the strength and rigidity of the side frame can be further increased.

According to the invention described in claims 7 and 8, in addition to the effects of the invention described in any one of claims 1 to 6,
The rear extension part where the plate and the pipe structure part extend rearward from the front surface of the rear frame part is joined to the rear wheel support frame part, so that the input load transmitted from the rear wheel via the rear wheel support frame part is However, a side frame structure having high strength and rigidity can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a side frame structure according to a first embodiment.

FIG. 2 is a partial perspective view of a side frame.

FIG. 3 is a front sectional view of a side frame.

FIG. 4 is a perspective view of a vehicle body frame.

FIG. 5 is a schematic plan view of a vehicle body frame.

FIG. 6 is a side view of the forklift.

FIG. 7 is a partial perspective view of a side frame according to the second embodiment.

FIG. 8 is a front sectional view of a side frame.

FIG. 9 is a front sectional view of a side frame according to a third embodiment.

FIG. 10 is a front sectional view of the same side frame.

FIG. 11 is a front sectional view of another example of a side frame.

FIG. 12 is a front sectional view of another example of the side frame different from FIG. 11;

FIG. 13 is a front sectional view of another example of the side frame different from FIG. 12;

FIG. 14 is a front sectional view of another example of the side frame different from FIG. 13;

FIG. 15 is a partial front view of a conventional side frame structure.

FIG. 16 is a partial front view of a conventional side frame structure.

FIG. 17 is a side view showing a conventional side frame structure.

[Explanation of symbols]

1 ... forklift as an industrial vehicle, 2 ... body, 8 ...
Front wheel, 9 Rear wheel, 10 Battery room as storage room, 2
0: front frame part, 30: rear frame part, 40
... Bottom frame part, 50 ... Side frame, 50a ...
Concave portions, 50b, 50c, 50d, 50e: pipe structure portion, 51: upper side plate as a plate material for determining the upper end line shape of the side frame, 53: plate material for determining the upper end line shape of the side frame, and upper side plate as a flat plate material , 51a, 51b, 53a, 53b
... Ribs, 52. Plates, lower side plates as thin plates, 51c, 52c. Bending ends, 54. Side cross plates as plate and thick flat plates, 55. Side plates as plate, 56. Pipes Material, 60: filler, F: body frame.

Claims (8)

(57) [Claims] A left and right side portion of a vehicle body is formed between a front frame portion and a rear frame portion which are provided upright in front of and below a bottom frame portion forming a bottom portion of a body frame of an industrial vehicle, and a housing chamber is formed therein. A side frame structure of an industrial vehicle that is connected in a state where the front frame portion and the rear frame portion are directly connected to the front frame portion and the rear frame portion, and an upper end line of a side frame of the plate material. A plate defining a shape is provided integrally with at least one of the plate members in a state where the plate member extends at least partially upward, and a seam is provided between the front frame portion and the rear frame portion. possess a rather extended by pipe structure, plate which determines the upper line shape of the side frame,
The part extending upward from the pipe structure is
The central part in the front-rear direction corresponding to the accommodation room is recessed downward
Side frame structure of industrial vehicle to have a recess. 2. The apparatus according to claim 1, wherein the plate material comprises a plurality of sheets, and at least two
Are overlapped with the top and bottom partly
And the upper and lower two
A plurality of plate members including plate members form the pipe structure.
The industrial vehicle according to claim 1, wherein the industrial vehicle is
Side frame structure. 3. The bent ends of the two plate members are vertically up and down.
The pipe structure is joined by being partially overlapped.
3. The industrial vehicle according to claim 2, wherein a structure is formed.
Side frame structure. 4. The plurality of pipes forming the pipe structure.
At least one of the plate materials is a thin plate material, and the one
Bending to form the pipe structure only on the plate
Part is formed, and the other sheet material except the one sheet material is two sheets.
A flat plate, and one of the two flat plates is thick.
Between the thin plate material and the flat plate material,
The pipe structure is formed by joining
A side frame structure for an industrial vehicle according to claim 2.
Build. 5. A bottom part of a body frame of an industrial vehicle.
Front frame standing before and after the bottom frame part
The left and right sides of the vehicle body are formed between the
Products that are connected together with compartments inside
A side frame structure of an industrial vehicle, wherein the front frame portion and the rear frame portion have front and rear ends.
One or more plate members directly connected to the parts, and the upper end line shape of the side frame among the plate members is determined.
With the plate material extended at least partially upward, the plate
The chlorofluorocarbon, provided integrally with at least one of the
Joint between the rear frame and the rear frame
Pipe structure part extended without, the plate material is a plurality of, at least two plate materials are vertically
Joining each other so that they partially overlap each other when placed
And a plurality including the upper and lower two plate members at the joint portion.
Are joined so as to form the pipe structure portion, at least one of the plurality of plate materials forming the pipe structure portion is a thin plate material, and the pipe structure portion is formed only on the one thin plate material. A fold to form is formed,
The other plates except the one thin plate are two flat plates,
One of the two sheets of flat plate is a thick, industrial vehicle by bonding sandwiching the flat plate of the thick that has the pipe structure is formed between the flat plate and the thin plate Side frame structure. 6. The side frame structure in an industrial vehicle according to claim 1, wherein a filler is filled inside the pipe structure. 7. The plate member and the pipe structure portion have a rear extension portion extending rearward from a front surface of the rear frame portion, and the rear extension portion is provided on a rear wheel support frame portion supporting a rear wheel. side frame structure in <br/> industrial vehicle according to any one of claims 1 to 6 are joined. 8. A bottom frame portion constituting a bottom portion of a body frame of an industrial vehicle, a front frame portion and a rear frame portion erected before and after the bottom frame portion, and the front frame portion and the rear frame portion. An industrial vehicle comprising: a side frame having a side frame structure according to any one of claims 1 to 7, wherein the left and right side portions of the vehicle body are formed and the space is connected so as to define an accommodation room therein. Body frame.