JPS6217000A - Fork for forklift truck - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fork for a forklift truck, and more specifically, to a fork for a forklift truck that can reduce the weight of the fork due to a change in shape.

A typical fork for a forklift truck consists of an L-shaped body in side view, in which an off star/dig arm, which is formed as a loading arm, is integrated with an upright arm, which for that purpose is called a lifting arm. It is connected. To connect the lift arm to the lift trunk structure, the lift arm is provided with several attachment members, and such forks are usually used in pairs.

Lift forks may often be described differently by designating the off-metal/ding arm or longitudinal load arm as the blade and the upright arm as the shank.

Regardless of the descriptive name, the action is of course the same;
As expected, the changes in the construction of such forks from the time of first use and construction are very slight.

Of course, it is known that forks can be made in a number of different ways by forging and bending during a forging process to consist of a common oval shaped body.

The ends of the longitudinal load arms are tapered end to end from a point approximately midway through such arms, and the main body of the fork is of straight cross section and substantial size.

Significant variations in fork construction are clearly limited by the need to maintain the strength for lifting purposes that large cross-section forks normally have, and this cross-section is obviously supported by the heel, which includes the connection of the load arm and the lift arm. This is obviously of particular importance for load support purposes.

In some circumstances, the load arm itself may be constructed as a separate member and connected to the lift truck structure for certain uses.

In order to reduce in some way the cost of the fork, the present invention is directed to various shapes of the fork, the thickness and width of the fork being important, if lifting capacity is present, but mainly the thickness will be determined by those skilled in the art. This can be achieved with calculations that can be done.

Accordingly, the present invention is directed to various forms of fork configurations which, to the best of our knowledge, have at least hitherto not been implemented with respect to substantial capacity forks and which have heretofore been unknown on the market.

To briefly outline the general field of the invention and its background, the cost of a fork is determined by its weight and therefore the reduction in weight that can be made will obviously reduce such cost and in the final analysis its sale as well. The aim is to provide a non-conventional solution to the manufacture of forks, to the extent of reducing costs.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments illustrated in the accompanying drawings.

FIG. 1 shows a forklift truck, the front end of which is designated by 1, which is supported on running wheels 2 and which extends upwardly from the running wheels 2 and is connected in a suitable manner to a trunk. The mast 3 has an L-shaped fork control and a carriage member 5 having a suitably vertically extending rail section 6 at its upper end and a corresponding rail section 7 at its lower end. Pivoting frame 4 for lifting and lowering movements
are connected.

The fork shown in the side view in Fig. 1 has an L-shape,
It is designated by 8 and has a load arm section 9 extending in the .tau. longitudinal direction and a vertically extending lifting arm section 10, which are connected by a heel section 11.

The upper end of the lifting arm 10 is provided with a suitable hook 12, and another hook 13 is provided to engage with the vertically extending rail 7.

7. Regarding the loading arm 9 of oak 8, it is provided with a generally flat planar section 4 provided on its upper surface, and the lower side of the planar section 14 is provided with a relatively sharp edge indicated by reference numeral 16. A parabolic shape 5 is formed which extends in the heel part lit, which is the thickest part of the loading arm 9.

Surface 15 therefore has a parabolic shape when viewed from the side.

The lifting arm 10 is similarly formed, but in reverse.

The flat portion is the rear surface 16, and the surface extending forward is formed with a parabolic surface 17 shown in side view having a parabolic shape.

Of course, even though the shape of a parabola gives rise to a parabolic outline, its surface is flat.

With regard to Figure 2, which shows a fork with a somewhat different shape, reference numeral 1
A specially shaped load arm, indicated at 8, is formed with a flat surface 19 on its upper side for supporting the load;
and a lower surface 2 extending rearward in a plane parallel to the upper surface 19 from the tip 21 on the lower side until it connects with the heel portion.
It has another flat section extending its width by two squares.

Although the lifting arms are generally constructed in a conventional manner, these arms have been modified in the manner described below, as will be explained below.

The lifting arm is equipped with a normal head connecting member 5 at its upper end, and the head connecting member 5 has a well-known hook shape, and if it is not formed integrally with the arm, the arm can be attached by welding. Let's go.

A conventional hook member is provided at the lower end of the arm near the heel of the fork.

The difference in this fork is due to its construction, in which the loading arm is approximately channel-shaped, including a channel area I;
The channel section n is shown in FIG. 4 with respect to a load arm 18 positioned between edges 28a and 29a, respectively.

The web material in the groove area n therefore consists of a clearly reduced cross-section compared to the usual 7 oak thickness as indicated by the arrow marked with a blade, the width of which is indicated by the extending arrow marked 31. There is.

The lifting arm U is similarly formed and has a flange 3 with corresponding ends Ml 32 a and 331 as shown in FIG.
2 and okara, and the open area of the channel part is indicated by the reference numeral.

Furthermore, figure g3 shows how the channel/channel area should be cut, and the channel area is 7. Consisting of a channel-shaped section of each arm with an oak heel section Z, the fork consists of the best shape that matches the rest of this fork, but the heel section is clearly a rigid vertical section. have. -- This general shape fork is usually the most common size for all purposes Q? Therefore, the ratio is essentially 2:1, for example, about 48 inches/inches long. It is a fork consisting of a loading arm and an elevating anise wing with a height range of inches.

The channel shape of each arm is such that each arm requires a lifting capacity equivalent to that allowed for the fork, which is a rigid shape and a normal shape of equal size with respect to the length of the load arm and the loft of the lifting arm. For such purposes, calculations can be made under various constraints so that the maximum possible distance can be extended to match the load carrying capacity of the fork.

As shown in FIG. 2, the cargo anise 18 actually has a channel-shaped portion on its underside, as shown in FIG. 1 and indicated by the dotted line A in FIG. When configured as a surface having a flag line shape, the shape indicated by point aB in FIG. Ru.

In fact, by initially forming a fork as shown in FIG. 1 with parabolic surfaces 15 and 17, a reduction in fork weight of about 101 can be achieved compared to conventional forks.

Furthermore, if the channel-shaped fork of FIG. 2 is provided, a saving of at least 10% can likewise be provided.

The second parabolic surface M and B have a channel portion.
By combining the shapes shown in the figure, a weight saving of approximately 20% is achieved.

Such weight savings are in fact extremely significant and clearly reduce manufacturing costs, allowing the fork to be sold at less cost.

The fork shown in FIG. 6 has a parabolic section along with a parabolic shape on the rear surface of the lifting arm, designated a, so that the lifting arm has a different profile. The fork's cargo arm is connected to the lifting arm by an integrated heel.

Although this fork shape is necessary due to manufacturing issues, the basic parabolic shape is used for the same purpose, namely to save weight. As such, it has a similar channel shape for both arms, so that weight savings can be similarly achieved.

The aim of the invention is with respect to weight saving, other cross-sectional shapes can be made which also achieve weight reduction, the thickness of the loading arm and the lifting arm is a controlling factor in the lifting strength, and A special configuration is the overall evaluation of the invention.

So if your fork is @4 inches and about 1 3/4 inches thick, you can make a fork that is 3 inches wide and 2 inches thick, and this fork will have the same lifting capacity and lift It has weight savings achieved without having to sacrifice any capacity.

In addition, Vcll is more strict in terms of weight savings! As a result of the analysis of these relationships, the present invention has certain formulas suitable for determining some basic dimensions of the fork with respect to the cross-sectional area of the load arm at the center of load.

The arbitrary dimensions of the fork are predefined and no real consideration is given to the capacity of the machine to which the fork is fitted and operated to carry out the action of the fork.

In practice, the machine has a certain rated capacity, but the fork has a somewhat larger capacity depending on the size of the supporting rods, which are formed to support loads with a larger cross-section than this is actually required. is determined in proportion to. Therefore, a considerable amount of weight is built into one orc.

Forks are used and i machines cost from 2000 bonds to 14.
Classified according to load carrying capacity, which ranges from up to 1,000 lbs., forks are generally much larger beyond this range, with larger trench cross-sections as the machine is constructed of larger capacities.

Fixed capacity machines should have suitable forks specifically sized using a formula in which the width and thickness of the fork, along with the load of the lift truck, are the determining factors. ' For example, in the present invention, a suitable formula is that the cube of the thickness multiplied by a constant of 2.5 is 0.0036 times the load. - In practical terms, the load is equal to the truck rated capacity divided by 2 mo, taking into account the fact that two 7 oaks are attached to the forklift truck and the cross section of the fork is exposed.

Thereby, the fork can be dimensioned by inserting the required dimensions into the equation and thus ascertaining the cross-sectional area at the center of load of the fork which controls the capacity conditions of the forklift truck with which the fork is associated.

By adopting this method, weight savings can now be shown to be achieved in even greater amounts.

- As an example, a currently available fork with a width of IQQ and a thickness of 45 mm has a rated capacity of 3,430 bonds for each 7 oak at its swing load center. Since lift trucks are rated in thicker 1000 or 2000 Bond increments from 2000 Bond capacity, it is clear that an excess load carrying capacity of 430 Bond for each fork is provided when used in a 6000 Bode lift truck. It is.

Assuming that the fork is equipped according to the inventor's formula, a fork with a relationship of 45B x 100 dishes would be 43.
The cross section of 0wX 95.6mm can be reduced and the load for which the machine is designed can be controlled.

Therefore, to supply forks for various forklift truck rated capacities, a weight reduction of 14.596
The tests are conducted on forklift trucks in the range of 000 to 14,000 bond capacities.

However, what should be pointed out is the lifting capacity of the fork.
Although the ki-take capacity is not acted upon in the opposite direction due to its shape, it may destroy the fork or otherwise cause additional deflection under maximum load).

[Brief explanation of the drawing]

FIG. 1 is a partial side view showing a conventional two-wheel lift truck supporting the fork of the present invention; FIG. 2 is a side view of a different type of fork showing another embodiment of the present invention; FIG.
4 is a longitudinal sectional view of the fork shown in FIG. 2 showing an embodiment with a constant weight reduction; FIG.
Figure 5 is a cross-sectional view of the fork's lifting arm along line 5-5 in Figure 2; It is a side view of a fork. In the figure, 1 is a forklift truck, 4 is a pivot frame, 8 is a fork, 9, 18.35 is a loading arm, 1
0, 24.36 are lifting arms, 15, 17 are parabolic surfaces, n is channel area, 2B, 29, 32, 3
3 is a flange, and the tool is a channel area.

Claims (7)

[Claims] (1) A fork for a forklift truck having a fork body consisting of a load arm connected at one end to a lifting mechanism to support a load, in which the fork body is integrally provided with a lift arm extending from the load arm, and the lift arm is connected to the lift arm. has parabolic-shaped surfaces on its sides, and the loading arm is formed from a channel-shaped cross-section having an opening at at least one end and extending substantially over the entire length of the loading arm; 1. A fork for a forklift truck, comprising a flange extending across the fork, the flange having a parabolic surface. (2) A patent claim characterized in that the loading arm is constituted by a channel-shaped cross section with an open end and a flange extending over substantially the entire length of the loading arm, the flange having a parabolic surface. A fork for a forklift truck according to item 1. (3) The elevating arm has a flange that extends over almost the entire length of the elevating arm and has a channel-shaped cross section with an open end, and the flange of the channel-like cross section is provided with a parabolic surface. A fork for a forklift truck according to claim 1. (4) A fork for a forklift truck consisting of an L-shaped fork body having a loading arm and a lifting arm integrally connected to the loading arm and attached to the lifting mechanism of the forklift truck, in which both arms are Claim 1 comprising a channel-shaped cross-section extending over substantially the entire length, one of the arms being provided with a flange that is open at least at one end and extends over substantially the entire length thereof. Forks for forklift trucks as described in section. (5) The fork for a forklift truck according to claim 4, wherein at least one flange of the arm is provided with a parabolic edge on a side surface. (6) A patent claim characterized in that, in a fork for a forklift truck having a predetermined lifting capacity, the optimum cross-sectional area of the fork at the center of the load is directly related to 1/2 of the rated capacity of the lift truck by a factor of 0.036. A forklift fork according to item 1. (7) The optimum dimension of the cross section of the fork at the load center is determined by the formula KT^3=0.0036L, where K is 2.5, T is the thickness, and L is 1/2 of the rated capacity of the forklift truck. Claim No. 6 which states:
Forks for forklift trucks as described in section.