JP2659871B2 - Forklift load detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to related to a load detecting apparatus for a forklift, and more particularly a load detector shock, suitably protected from vibration or the like during traveling, moreover Te optimum height odor
About the things that can make a total amount.

[0002]

2. Description of the Related Art In a freezer, a refrigerator, and the like, a storage price and the like are calculated based on the weight of a load to be stored. Further, since the transaction price is often calculated based on the weight, it is necessary to grasp the weight of the load in pallet units.

However, when a load is carried in from a truck using a forklift, if the weight of the load is measured with a weighing scale each time, there is a problem that the carrying-in operation takes a long time.

Therefore, conventionally, the weight of the load
It has been proposed to measure the volume using a strain gauge.
You. For example, as shown in FIGS.
2 is a fork 6 as a load support for the forklift 1
And a movable plate 5 for supporting the
The relative displacement in the vertical direction with respect to the fixed plate 4 to be stopped is
Strain gauge 10 as a weight detector provided between
Is configured to be detected.

[0005] The lift bracket 3 is
Roller 11 and can be moved up and down by a lift cylinder (not shown).
Connected to one end of the chain to be moved up inside the mast 2
It moves down, and the lift cylinder is stationary.
Can stop at The lift bracket 3 is located on the front
The finger bars 3A and 3B are welded up and down
The fixed plates 4 are locked to the finger bars 3A and 3B.
It is.

The fixed plate 4 has a leaf spring 7 on its front surface,.
7, while being elastically connected to the movable plate 5 via
The leaf spring 7 is covered with reinforcing plates 8 from above and below,
The displacement amount in the vertical direction is configured to be very small. Left and right
A pair of forks 6, 6 are melted above and below the front surface of the movable plate 5.
The upper and lower finger bars 5A and 5B
You.

Also, from the fixed plate 4 and the movable plate 5,
Upper and lower brackets 9A and 9B are formed, and between them
The strain gauge 10 is held by bolts or the like. Therefore, the load W
When the movable plate 5 is placed on the fork 6, the movable plate 5
And the strain gauge 10 is pulled down by a relatively small amount.
It elastically deforms under tension load. This elastic deformation is measured by a strain gauge 1
Detected by a change in electrical resistance of 0, and perform predetermined processing
As a result, the weight of the load W is
This is displayed on the display 13 provided at the seat.

[0008]

THE INVENTION Problems to be Solved] However, Four
With the load W placed on the fork 6 of the clift 1, for example,
When the fork is lowered from the altitude to the lowest position,
The impact of the fork 6 colliding with the surface is transmitted to the strain gauge 10.
And cause a failure. Also,
In addition, the vibration during running of the forklift 1 is constantly distorted.
Will be transmitted to a total of 10
Not a good one. Also, the fork height at the time of weighing is
If they differ, a weighing error will occur depending on the fork height.
There is also a problem that it is not possible to accurately measure the load
You. The present invention has been made in view of such a problem, and has been developed.
The purpose of this is to use the impact during
Optimally protects the strain gage from internal vibrations, etc.
Load detector that can measure the load only at the workpiece height
Is to provide.

[0009]

According to a first aspect of the present invention, there is provided a fixing plate engaged with a front surface of a lift bracket provided to be movable up and down with respect to a mast of a forklift; A movable plate for supporting a load support provided in a state capable of being relatively displaced in a vertical direction with respect to the fixed plate in a forward direction, and detecting the relative displacement between the fixed plate and the movable plate. A load detecting device for a forklift provided with a weight detecting device for detecting the weight of the load loaded on the load supporting device, and
To prevent the movable plate from being relatively displaced.
And the height of the load support is above the ground level,
One of the lock hands
Unlocking means for releasing the step and displacing the movable plate.
This is a load detection device for a forklift, which is provided.

[0010]

The weight of a load loaded on a load support such as a fork can be detected by displacing the movable plate with respect to the fixed plate, and the displacement can be detected by a weight detector. It is possible to do.

In addition, the fixed plate and the movable plate are arranged in front and rear, and a weight detector is arranged between the fixed plate and the movable plate.
The size of the device in the vertical direction can be reduced, and for example, it can be formed to have substantially the same height as the lift bracket.

Further, in the present apparatus, the lift bracket of a conventional forklift can be used as it is,
Installation is extremely easy and inexpensive.

Further, only when the load support of the forklift is lifted to a predetermined height, the fixed plate and the movable plate can be relatively displaced, and the load of the load can be detected. On the other hand, for example, when the load support is in contact with the ground,
Since the fixed plate and the movable plate are mechanically fixed, even if the load support collides with the ground, the impact is not transmitted to the weight detector and the device can be prevented from being damaged.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, the same parts as those in the prior art are denoted by the same reference numerals. The load detecting device 12 has the same configuration as that described above, and a description thereof will be omitted. In this embodiment , the relative displacement between the fixed plate 4 and the movable plate 5 is changed.
A lock means for preventing the position of the fork , and detecting that the height of the fork 6 is within an arbitrary height range from the ground, and
And the movable plate 5 can be displaced with respect to the fixed plate 4.
A dog 20 is fixed to the mast 2 and the dog 2 is used as the unlocking means.
An example is shown that includes a lever 15 that swings when it comes into contact with zero.

The movable plate 5 is fixed to the fixed plate 4.
As a locking means that can prevent relative displacement of the movable plate 5, a slide pin 16 that can be inserted into a hole 19 formed in the movable plate 5 is shown .

The dog 20 is fixed to one side surface of the mast 2 over a predetermined length, and both ends thereof are cut off in a tapered shape so that the lever 15 can move smoothly.
A support piece 17 is fixed to the back surface of the fixed plate 4, and the support piece 17 rotatably supports a substantially intermediate portion of the lever 15 having a roller 14 at the tip.

A slide pin 16 is loosely supported at one end of the lever 15. The mast 2 is a mast on the fixed side in this example.

The slide pin 16 is supported by the fixed plate 4 so as to penetrate therethrough, and the tip of the slide pin 16 is inserted into a hole 19 formed in the movable plate 5. Also, the slide pin 16
A flange 16A is formed in the vicinity of the front end of the spring, and a spring 18 is elastically inserted between the flange 16A and the fixing plate 4.

Therefore, the slide pin 16 is constantly urged toward the movable plate 5 and the hole 1 of the slide pin 16 is
By the insertion into the fixed plate 9, the fixed plate 4 and the movable plate 5 are locked so that no relative displacement occurs.

When the fork 6 is at the lowest position, the fixed plate 4 and the movable plate 5 are fixed by the slide pins 16 as shown in FIG. Therefore, even if the fork 6 collides with the ground, the impact is not transmitted to the strain gauge 10, and the weighing of the load is also prohibited.
You.

Next, when the fork 6 is raised, FIG.
As shown in FIG.
Abuts on the dog 20 provided in the first position . And lever 15
Slide pin 16 by the swing of the spring 18 by anti Ji slides to the left in the figure, locking means release
As a result, the fixed plate 4 and the movable plate 5 are elastically supported by the leaf spring 7, and the relative displacement thereof can be measured by the strain gauge 10.

[0022] In addition, if further increase the fork 6
When the roller 14 of the lever 15 separates from the dog 20, the slide pin 16
But is inserted into the hole 19 is removed the elastic deformation of the strain gauge 10, Ru fixed Siu the fixed plate 4 and the movable plate 5 again.

As described above, the fixed plate 4 and the movable plate 5 are
As a result, the vibration during traveling of the forklift is not transmitted to the strain gauge 10, and the load cannot be measured.

[0024] have been described in detail the real施例of more than the present invention,
The range of the fork height where the load can be measured may be set to a range where the measurement error is minimized by variously adjusting the mounting position and the length of the dog 20 according to the forklift to be used.

In this embodiment, when the lever contacts the dog 20 , the height of the fork is detected by the swing of the lever 15 , and
Although Tsu has a configuration for releasing the click, in addition to this, for example, and detects the height of the fork at the limit switch, sticking the tape to the mast side, a magnetic sensor provided on the fixed plate side Rutotomoni, Slide after receiving this signal
The pin equivalent is connected to an actuator (for example, an electric
Cylinder, etc.).
Wear.

Further, in the above-described embodiment, a pair of left and right forks is exemplified as the load support. However, various other attachment devices used for forklifts may be used without departing from the scope of the present invention. It can be suitably adopted also when it is mounted.

[0027]

According to the present invention, as a result of employing the above configuration,
The load amount can be detected simultaneously with unloading, and the vertical dimension of the load detection device can be reduced. In addition, as it can be easily attached to and detached from a lift bracket of an ordinary forklift, there is no need for modification required for attachment, and the cost is low.

[0028] Also, forklift, upon lifting up the load to a range of predetermined height, between the fixed plate and the movable plate
Since the lock is released and the two can be displaced relative to each other and the load can be weighed, the strain gauge is destroyed due to the fork colliding with the ground at the lowest position or vibration during traveling etc. Such a situation can be prevented. Also, the fork height when weighing a load is always within a certain range
As a result, it is possible to perform accurate weighing while preventing variations in weighing errors.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a side view showing one embodiment of the present invention.

FIG. 3 is a side view of a forklift provided with a conventional load detecting device .

FIG. 4 is a side view showing a conventional load detecting device .

FIG. 5 is a plan view showing a conventional load detecting device .

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Forklift 2 Mast 3 Lift bracket 4 Fixed plate 5 Movable plate 6 Fork 7 Plate spring 8 Reinforcement plate 9A Bracket 9B Bracket 10 Strain gauge 12 Load detector

Claims (1)

(57) [Claims] A fixed plate fixed to a front surface of a lift bracket provided to be movable up and down with respect to a mast of a forklift; and a state in which the fixed plate can be displaced in front of the fixed plate in a direction perpendicular to the fixed plate. A movable plate for supporting the load support provided, and detecting the relative displacement between the fixed plate and the movable plate to detect the weight of the load loaded on the load support. a load detecting device for a forklift comprising providing a weight detecting device, from the movable plate with respect to the fixed plate is relatively displaced
Locking means and the height of the load support are above ground level and are predetermined
The lock means is released
Lock release means for displacing the movable plate is provided.
A load detecting device for a forklift.