JP2012020814A - Forklift and device for measuring gravity center - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure a vertical gravity center of a load carried by a forklift.SOLUTION: Load cells 14-14are arranged on a pair of fork prongs 11, 11at intervals in the front-back direction, and an inclination sensor 15 is arranged on one fork prong 11of the pair to detect the angle of inclination so that the vertical gravity center of a container 13 as the load placed on the fork prongs 11, 11may be computed based on detected outputs of the load cells 14-14and the detected outputs of the inclination sensor 15.

Description

  The present invention relates to a forklift and a center-of-gravity position measuring apparatus capable of determining a center of gravity position of a load to be transported, particularly a center of gravity position in a vertical direction.

  In general, a forklift has a mast that supports a pair of forks (claws) that can be raised and lowered at the front of the vehicle body, and carries a cargo handling work by carrying a cargo such as a container for logistics on the fork. .

  In such a cargo handling operation, if the center of gravity of the load placed on the fork is eccentric, there is a risk that the vehicle loses balance and rolls over during traveling. For this reason, a forklift has also been proposed in which the left and right eccentric amounts of the load are obtained and displayed (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 5-65999

  However, in the above-mentioned Patent Document 1, only the right and left eccentric states of the load with respect to the center of the vehicle body are obtained and displayed, and the center of gravity position of the load in the height direction, that is, the vertical direction is not taken into consideration at all.

  In a forklift, there is a case where the load placed on the fork is lifted high, and in such a case, if the vertical center of gravity of the load is eccentric upward, the risk of losing balance and overturning increases. .

  Also, in the operation of transport machinery such as trucks and ships that carry luggage, the center of gravity in the vertical direction of the luggage is unknown, so depending on the load status of the luggage, the center of gravity may be unbalanced and operating In addition, there are cases where the transport machinery is tilted or the load collapses, hindering safe operation.

  The present invention has been made in view of the above points, and an object of the present invention is to make it possible to obtain the position of the center of gravity in the vertical direction of a load transported by a forklift.

  In order to achieve the above object, the present invention is configured as follows.

  (1) A forklift of the present invention is a forklift provided with a mast tilted in the front-rear direction and a fork supported by the mast so as to be able to be raised and lowered. And at least two load sensors for detecting a load; and a calculation means for calculating a vertical center of gravity position of the load based on a detection output of the load sensor and an inclination angle of the fork accompanying the inclination of the mast. ing.

  Luggage refers to an article, such as a container, that is carried by a forklift.

  The position of the center of gravity in the vertical direction of the baggage calculated by the calculation means may be displayed or printed by an external display or printer, or the forklift may be provided with a display or printer.

  According to the forklift of the present invention, the vertical center of gravity position of the load is calculated based on the load of the load detected by the load sensor provided on the fork and the inclination angle of the fork. Can be grasped. As a result, when the load is transported by the forklift, safe traveling according to the eccentric state of the load in the vertical direction can be performed, and a rollover accident or the like can be prevented. Further, when loading a load on a transport machine such as a truck or a ship by the forklift, it is possible to load the load in consideration of the balance of the center of gravity of the load, and the transport machine can be safely operated.

  (2) In another embodiment of the forklift of the present invention, the fork is provided with a pair of left and right forks, and each fork is provided with two load sensors along the front-rear direction, and at least one of the forks includes An inclination sensor for detecting an inclination angle of the fork is provided, and the calculation means is configured to determine a horizontal gravity center position and a vertical gravity center of the load based on the detection output of the load sensor and the detection output of the inclination sensor. Each position is calculated.

  According to this embodiment, each of the pair of left and right forks is provided with two load sensors, so the load can be detected by supporting the load by a total of four load sensors. Based on the detection output of the load sensor and the detection output of the tilt sensor, the center of gravity of the load in the horizontal direction and the position of the center of gravity in the vertical direction are calculated. Become. As a result, when the load is transported by the forklift, it is possible to perform safer traveling according to the eccentric state of the load in the vertical and horizontal directions.

  (3) In a preferred embodiment of the forklift according to the present invention, the calculation means is configured to detect the output of the load sensor when the fork on which the load is placed is in a horizontal state or an inclined state, and in the inclined state. Based on the inclination angle at a certain time, the center-of-gravity position in the vertical direction of the load is calculated.

  According to this embodiment, the detection output of the load sensor when the fork loaded with the load is in a horizontal state, the detection output of the load sensor when the fork loaded with the load is in an inclined state, and the detection output of the tilt sensor Based on this, it is possible to calculate the vertical center of gravity position of the load.

  (4) In another embodiment of the forklift according to the present invention, the forklift includes output means for outputting data of the center of gravity position calculated by the calculation means.

  The output means preferably outputs the data on the center of gravity position of the package in at least one of display, sound, and printing. The data of the center of gravity position may be the center of gravity position itself, or the amount of deviation of the center of gravity position, that is, the amount of eccentricity.

  According to this embodiment, since the data of the gravity center position of the luggage calculated by the computing means is output by the output means, the driver can easily grasp the gravity center position of the luggage and perform safe traveling. It becomes.

  (5) A center-of-gravity position measuring apparatus according to the present invention is a center-of-gravity position measuring apparatus equipped in a forklift that includes a mast tilted in the front-rear direction and a fork supported so as to be movable up and down on the mast. A fork attachment having at least two load sensors that are detachably attached and detect a load of a load placed on the fork and an inclination sensor that detects an inclination angle of the fork, a detection output of the load sensor, and the Calculation means for calculating the horizontal center of gravity position and the vertical center of gravity position of the load based on the detection output of the tilt sensor, respectively.

  According to the center-of-gravity position measuring device of the present invention, the center-of-gravity position in the vertical direction of the load is calculated based on the load of the load and the inclination angle of the fork detected by the load sensor and the tilt sensor of the fork attachment. It becomes possible to grasp the position of the center of gravity in the vertical direction. Also, by attaching a fork attachment to the fork of an existing forklift and mounting a computing means on the vehicle body, it is possible to obtain the center of gravity position of the load in the vertical direction, and the existing forklift can have a function of measuring the center of gravity. it can.

  Thus, according to the present invention, the position of the center of gravity in the vertical direction of the load is calculated based on the load of the load detected by the load sensor provided on the fork and the inclination angle of the fork. It is possible to grasp the position of the center of gravity in the vertical direction. As a result, when the load is transported by the forklift, safe traveling according to the eccentric state of the load can be performed, and a rollover accident or the like can be prevented. In addition, when loading a load on a transport machine such as a truck or a ship using the forklift, it is possible to load the load in consideration of the balance of the center of gravity of the load, and the transport machine can be operated safely.

FIG. 1 is a side view of a forklift according to an embodiment of the present invention. FIG. 2 is a block diagram illustrating a configuration of the gravity center position measuring apparatus. FIG. 3 is a plan view showing a schematic configuration of a pair of fork portions in FIG. FIG. 4 is a side view showing a schematic configuration of a pair of fork portions in FIG. 1. FIG. 5 is a front view showing a schematic configuration of a pair of fork portions in FIG. 1. FIG. 6 is a schematic plan view of the fork portion showing the center of gravity position in the front-rear direction. FIG. 7 is a schematic plan view of the fork portion showing the position of the center of gravity in the left-right direction. FIG. 8 is a diagram showing the action of force when the fork is in a horizontal state for explaining the principle of obtaining the vertical center of gravity position of the load. FIG. 9 is a diagram showing the action of force when the fork is tilted for explaining the principle of obtaining the center of gravity position of the load in the vertical direction. FIG. 10 is a diagram showing the relationship between the support reaction force detected by the load cell in a state where the fork is inclined at an angle θ and the support reaction force in the vertical direction that should be detected originally. FIG. 11 is a diagram illustrating a display example of the display unit. FIG. 12 is a side view showing a state in which an existing forklift is equipped with a center-of-gravity position measuring device. FIG. 13 is a diagram showing a fork and a fork attachment. FIG. 14 is a block diagram of a center-of-gravity position measuring apparatus according to another embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a side view of a forklift according to an embodiment of the present invention.

  The forklift 1 of this embodiment includes a vehicle body 4 with wheels 2 and 3 attached to the front and rear. A seat 5 on which a driver is seated is provided on the vehicle body 4, and a handle 6, an operation lever 7, and the like are provided. A head guard 8 is provided so as to be disposed and surround them.

  A mast 10 that tilts in the front-rear direction by the expansion and contraction of the tilt cylinder 9 is erected at the front portion of the vehicle body 4, and a pair of left and right forks (claws) 11 for loading a load is supported on the mast 10. . The fork 11 is moved up and down by a lift cylinder 12 provided along the mast 10.

  In the forklift 1 having such a configuration, when carrying out the cargo handling work, after the fork 11 is lowered and the load is loaded, the fork 11 is placed in a horizontal state or a state in which the fork 11 is inclined to the rear side, and the vehicle body 4 is run to load the load. Is conveyed to a predetermined position.

  The forklift 1 according to this embodiment includes a center-of-gravity position measuring device that measures the center-of-gravity position in the horizontal direction and the center-of-gravity position in the vertical direction of the load placed on the pair of forks 11.

  FIG. 2 is a block diagram showing the configuration of the center-of-gravity position measuring device provided in the forklift 1.

The center-of-gravity position measuring device 25 of this embodiment includes load cells 14 _{1 to} 14 ₄ as four load sensors that detect the load of a load placed on the fork 11, an inclination sensor 15 that detects an inclination angle of the fork 11, The A / D converter 16 for A / D converting the detection output of each of the load cells 14 _{1 to} 14 _{4 and} the detection output of the inclination sensor 15 and the A / D input via the input / output (I / O) circuit 19. Based on the digital output from the D converter 16, calculation means 17 for calculating the horizontal center of gravity position and the vertical center of gravity position of the package as will be described later, and a display for displaying the data of the center of gravity position as the calculation result Part 18. The computing means 17 is constituted by, for example, a microcomputer including a CPU 20 and a memory 21. The load sensors 14 _{1 to} 14 ₄ and the inclination sensor 15 are provided on the fork 11 as described later. The display unit 18 that displays the data of the center of gravity position is installed at a position where the driver can visually check.

  3 is a plan view showing a schematic configuration of a pair of forks 11 in FIG. 1, FIG. 4 is a side view thereof, FIG. 5 is a front view thereof, and each figure shows a container 13 as a load. Is also shown. In each figure, G indicates the position of the center of gravity of the container 13.

A pair of forks 11 is composed of a first fork 11 _R on the right side, and the second fork 11 _L on the left. Each fork 11 _R , 11 _L includes horizontal portions 11 _Rh , 11 _Lh extending in the horizontal direction and vertical portions 11 _Rv , 11 _Lv extending in the vertical direction in the horizontal state where the mast 10 is not inclined, It is configured in an L shape.

The horizontal portions 11 _Lh and 11 _Rh of the forks 11 _L and 11 _R are each provided with the two load cells 14 _{1 to} 14 ₄ spaced apart in the front-rear direction (the left-right direction in FIGS. 3 and 4). ing. Specifically, the first fork 11 _R of the right side, first, second load cell 14 _1, 14 _{whereas 2} is provided, the second fork 11 _L on the left, third, fourth load cell 14 _3, 14 ₄ is provided. The load of the container 13 placed on the forks 11 _R and 11 _L is configured to be supported by the _four load cells 14 _{1 to} 14 ₄ .

Further, the inclination sensor 15 described above that detects the inclination angle of the forks 11 _R and 11 _L is provided near the bent portion of the first fork 11 _R.

  Next, the procedure of the center-of-gravity position calculation process by the calculation unit 17 of the above-described center-of-gravity position measurement device 25 in FIG. 2 will be described.

First, a procedure for obtaining the horizontal position of the center of gravity of the container 13 will be described. The horizontal gravity center position is calculated based on the weight of the container 13 detected by each of the load cells 14 _{1 to} 14 ₄ when the forks 11 _L and 11 _R are in a horizontal state.

  FIG. 6 is a schematic plan view corresponding to FIG. 3 described above showing the center of gravity position of the container 13 in the front-rear direction (left-right direction in FIG. 6).

As shown in FIG. 6, the distance in the front-rear direction between the second and fourth load cells 14 ₂ and 14 ₄ on the front side and the first and third load cells 14 ₁ and 14 ₃ on the rear side is D1, and the second the fourth load cell 14 _2, 14 ₄ in total W _F of the weight to be detected, respectively, the first rear third load cell 14 _1, 14 a total weight which are respectively detected by the ₃ W _B, the rear first 1, where the distance from the third load cell 14 ₁ , 14 ₃ to the center of gravity G of the container 13 is X _G ,
X _G × W _B = (D1−X _G ) × W _F
The relationship is established.

Therefore, the following formula:
X _G = D1 × W _F / (W _F + W _B )
It is possible to obtain the gravity center position X _G in the longitudinal direction of the container 13 by.

  FIG. 7 is a schematic plan view corresponding to FIG. 3 described above showing the gravity center position of the container 13 in the left-right direction (up-down direction in FIG. 7).

As shown in FIG. 7, the distance between the left and right _third and fourth load cells 14 ₃ and 14 ₄ and the right and first right and left load cells 14 ₁ and 14 _{2 in} the left-right direction is D2, and the left and _{third third} and fourth load cells 14 ₃ and 14 ₂ are left and right. The total weight detected by the load cells 14 ₃ and 14 ₄ is W _L , the total weight detected by the first and second load cells 14 ₁ and 14 ₂ on the right side is W _R , and the first and second right sides are detected. If the distance from the load cells 14 ₁ and 14 ₂ to the center of gravity G is Y _G ,
Y _G × W _R = (D2−Y _G ) × W _L
The relationship is established.

Therefore, Y _G = D2 × W _L / (W _L + W _R ) is obtained. Here, since the weight _{W R + W L = W B} + W F of the container 13,
Y _G = D2 × W _L / (W _B + W _F )
Thus, the center-of-gravity position Y _G in the left-right direction can be obtained.

As described above, in the calculation means 17, the forks 11 _L and 11 _R are in a horizontal state, and based on the weight detected by each of the load cells 14 _{1 to} 14 ₄ , the front and rear direction and the left and right direction of the container 13, that is, the horizontal The center of gravity position in the direction is calculated and calculated.

  Next, the principle of obtaining the center of gravity position of the vertical method of the container 13 will be described with reference to FIGS.

FIG. 8 is a diagram illustrating the action of force when the container 13 is placed on the forks 11 _L and 11 _R and is horizontal. mg is the weight of the container 13, F ₁ is the supporting reaction force by the _first and third load cells 14 ₁ , 14 ₃ on the rear side, and F ₂ is by the second and fourth load cells 14 ₂ , 14 ₄ on the front side. The support reaction force, X _G is the distance in the front-rear direction (left-right direction in FIG. 8) between the first and third load cells 14 ₁ , 14 ₃ on the rear side and the center of gravity G of the container 13, and D 1 is the rear side The distances in the front-rear direction between the first and third load cells 14 ₁ and 14 ₃ and the front and second second and fourth load cells 14 ₂ and 14 ₄ are shown. The support reaction force F ₁ is equal to the sum of the weights detected by the first and third load cells 14 ₁ and 14 ₃ on the rear side, and the acting direction is opposite, and the support reaction force F ₂ is the first reaction force F ₂ on the front side. 2, equal to the sum of the weights detected by the fourth load cells 14 ₂ and 14 ₄ , respectively, and the acting direction is opposite.

  From the balance of forces in FIG.

F ₁ + F ₂ = mg (1)
Moreover, the following formula is established from the balance of moments.

mg × X _G = F ₂ × D1 (2)
FIG. 9 is a diagram showing the action of force when the container 13 is placed on the forks 11 _L and 11 _R and inclined by the angle θ. F ₁ ′ is the vertical support reaction force by the _first and third load cells 14 ₁ and 14 ₃ on the rear side, and F ₂ ′ is the vertical reaction force by the second and fourth load cells 14 ₂ and 14 _{4 on} the front side. The support reaction force, X _G ′ is the distance in the front-rear direction between the first and third load cells 14 ₁ , 14 ₃ on the rear side and the center of gravity G of the container 13, and X ₁ is the first, third third on the rear side. The distance along the inclined bottom surface between the load cell 14 ₁ , 14 ₃ and the intersection of the vertical line passing through the gravity center G of the container 13 and the bottom surface of the container 13, X ₂ passes through the intersection and the gravity center G of the container 13. The intervals along the inclined bottom surface between the line perpendicular to the bottom surface and the intersection of the bottom surface are shown.

The inclination angle θ of the forks 11 _L and 11 _{R is} an angle such that the container 13 does not shift backward due to the inclination, and is preferably within a few degrees, for example.

In FIG. 9, from the balance of moments,
mg × X _G ′ = F ₂ ′ × D 1 cos θ (3)
Here, when the forks 11 _L and 11 _R are inclined, the surface to which the load cells 14 _{1 to} 14 ₄ are attached is inclined, so that the support reaction force F ₁ ′ equal to the weight detected by the load cells 14 _{1 to} 14 ₄ is obtained. ', F ₂ ″ includes an error corresponding to the inclination of the load cells 14 _{1 to} 14 ₄ itself.

That is, as shown in FIG. 10, the support reaction forces F ₁ ″ and F ₂ ″ that are equal to the weight detected when the load cells 14 _{1 to} 14 ₄ are inclined at the angle θ are originally in the vertical direction to be detected. For the supporting reaction force F ₁ ', F ₂ '
F ₁ ″ = F ₁ 'cos θ
F ₂ ″ = F ₂ 'cos θ
It becomes.

Therefore, the support reaction forces F ₁ ′ and F ₂ ′ that should be detected can be calculated from the outputs F ₁ ″ and F ₂ ″ detected by the load cells 14 _{1 to} 14 ₄ by the following equation. That is, the weight error detected by the load cells 14 _{1 to} 14 ₄ can be corrected by the following equation.

F ₁ '= F ₁ ″ / cos θ
F ₂ '= F ₂ ″ / cos θ
Further, in FIG. 9, the fork 11 _L, 11 from the geometric relation during tilting of _R, the following equation holds.

X _G = X ₁ + X ₂ = (X _G '/ cos θ) + Z _G tan θ (4)
When Z _G is obtained from the above equations (1) to (4),
Z _G = [D1 / {(F ₁ + F ₂ ) tan θ}] (F ₂ −F ₂ 'cos θ) (5)
In the above equation, the distance D1 in the front-rear direction between the first and third load cells 14 ₁ and 14 ₃ on the rear side and the second and fourth load cells 14 ₂ and 14 ₄ on the front side is known, and the inclination angle θ is It can be measured by the inclination sensor 15. Since F ₁ , F ₂ , and F ₂ ′ are obtained from the detection outputs of the load cells 14 _{1 to} 14 ₄ , it is possible to obtain the vertical center of gravity position of the container 13, that is, the center of gravity height Z _G.

  As described above, in the calculation means 17 described above, the horizontal center of gravity (the center of gravity on the horizontal plane) and the vertical center of gravity (the center of gravity on the vertical plane) of the container 13, that is, the three-dimensional center of gravity. Calculate the position.

  In this embodiment, the amount of eccentricity from the center of the vehicle width at the center of gravity in the horizontal direction is displayed on the display unit 18 and the amount of eccentricity from the center in the vertical direction of the container 13 at the center of gravity in the vertical direction is displayed. I have to.

  For example, as shown in FIG. 11, in the display unit 18, the center of gravity position is lit by a display lamp composed of a plurality of LEDs or the like. That is, when the center of gravity is within the permissible range near the center, the center rectangular indicator lamp 18a is lit, and when the center of gravity is out of the permissible range and is decentered in the left-right direction, the left and right corresponding arrow-shaped displays are displayed. When the lamps 18b and 18c are turned on and the center of gravity is out of the allowable range and is decentered in the vertical direction, the corresponding arrow-shaped indicator lamps 18d and 18e on the upper and lower sides are turned on.

  In addition, when the gravity center position of the container 13 is eccentric upward, you may make it restrict | limit the raising / lowering height of the fork 11 according to the amount of eccentricity. Further, when the amount of eccentricity exceeds a predetermined value, a warning sound or the like may be notified.

  The display unit 18 is not limited to an indicator lamp, and may be a liquid crystal display unit. Further, the amount of eccentricity may be displayed as a numerical value or a bar graph, or the position of the center of gravity may be displayed as a graphic or graph instead of the lighting display by the indicator lamp. Further, the calculation means 17 may be connected to a printer via the I / O circuit 19 so that the data of the center of gravity position can be printed out. Alternatively, the calculation means 17 may be connected to a personal computer so that the data on the center of gravity can be tabulated and managed by the personal computer.

  As described above, the computing means 17 can calculate the weight of the container 13 as well as the center of gravity position, so that the weight data of the container 13 may be displayed and printed in addition to the data of the center of gravity position.

  As described above, the horizontal gravity center position and the vertical gravity center position of the container 13 are displayed on the display unit 18, so that the driver can check the eccentric state in the horizontal and vertical directions. As a result, when the driver carries the container 13 with the forklift 1, the driver can perform safe traveling according to the eccentric state, and can prevent a rollover accident or the like. In addition, when the container 13 is loaded on a transport machine such as a truck or a ship with the forklift 1, the transport machine can be safely operated by loading the container 13 in consideration of the balance of the center of gravity.

In this embodiment, the inclination sensor 15 is provided and the inclination angles of the forks 11 _R and 11 _L are detected. However, the inclination sensor 15 is omitted, and information on the inclination angle according to the operation of the tilt lever for inclining the mast 10 is used. Then, the center of gravity position may be calculated.

  Since some load cells have a tilt sensor and have a function of correcting an error due to tilt, the load sensor may be used to omit the tilt sensor 15.

(Embodiment 2)
In the above-described embodiment, the forklift 1 includes the center-of-gravity position measuring device 25 that measures the center-of-gravity position of the container 13. However, as another embodiment of the present invention, the forklift 1 has a function of measuring the center-of-gravity position of the container 13. A non-existing forklift may be equipped with a center-of-gravity position measuring device that measures the center of gravity of the container 13.

FIG. 12 is a side view showing a state in which a load cell or the like of the center of gravity position measuring device is mounted on an existing forklift 1a. In this embodiment, a pair of left and right forks 11 of the existing forklift 1a _R a, 11 _L a, the load sensor 14 _{1-14 4} and the tilt sensor 15 shown in FIG. 13 is provided, and one end outlet Are inserted into the opened sheath-like fork attachments 22 _R and 22 _L , respectively. Further, the calculation means 17 (not shown) connected to the load sensors 14 _{1 to} 14 ₄ and the inclination sensor 15 of the fork attachments 22 _R and 22 _L and the display unit 18 are mounted at appropriate positions on the vehicle body 4 of the forklift 1a. To do.

The fork attachments 22 _R and 22 _L are respectively inserted into the forks 11 _R a and 11 _L a of the existing forklift 1 a and attached with retaining pins and screws.

  In this way, the existing forklift 1a can be provided with a function of measuring the position of the center of gravity of the load.

  Other configurations are the same as those of the above-described embodiment.

(Embodiment 3)
In the above-described embodiment, the horizontal and vertical gravity center positions of the container 13 calculated by the calculation means 17 are displayed on the display unit 18 or printed out by a printer. As a form, as shown in FIG. 14 corresponding to FIG. 2 described above, an RFID writer 23 for writing the data of the center of gravity calculated by the calculation means 17 to the RFID tag 24 wirelessly in a non-contact manner is provided. 24 may be attached to the container 13.

  With this configuration, the forklift 1 calculates the gravity center position of the container 13 as described above, and then writes the data of the gravity center position to the RFID tag 24 attached to the container 13 by the RFID writer 23.

  Thus, since the data of the center of gravity is written in the RFID tag 24 of the container 13, the data of the center of gravity of the container 13 is read by the RFID reader when loading on a transport machine such as a truck or a ship. It becomes possible to load the vehicle so that the center of gravity becomes stable, and the safe operation of the transport machine becomes possible.

  As another embodiment of the present invention, data relating to the position of the center of gravity may be attached to the container 13 using a barcode, and may be read by a barcode reader.

(Other embodiments)
In each of the above-described embodiments, description has been made by applying to the container 13 as a load. However, the present invention is not limited to the container and can be applied to various items transported by a forklift. A pallet may be included.

In each of the embodiments described above, the load is supported by the _four load cells 14 _{1 to} 14 ₄ and the load is detected. However, as described with reference to FIGS. 8 and 9, the load is detected by two load sensors. The load may be detected in support. Alternatively, the load may be detected by supporting the load with three or five or more load sensors.

  The present invention is useful as a forklift.

1,1a forklift 9 tilt cylinder 10 mast _{11,11 R, 11 L, 11 R} a, 11 L a fork 13 container (cargo)
14 _{1 to} 14 ₄ Load cell 15 Tilt sensor 17 Calculation means 18 Display unit 22 _R , 22 _L Fork attachment 23 RFID writer 24 RFID tag

Claims (5)

A forklift comprising a mast tilted in the front-rear direction and a fork supported by the mast so as to be movable up and down,
At least two load sensors provided on the fork for detecting the load of a load placed on the fork;
Calculation means for calculating a vertical center of gravity position of the load based on the detection output of the load sensor and the inclination angle of the fork accompanying the inclination of the mast;
A forklift characterized by comprising: A pair of left and right forks is provided, each fork is provided with two load sensors along the front-rear direction, and at least one of the forks is provided with an inclination sensor for detecting an inclination angle of the fork,
The computing means computes the horizontal gravity center position and the vertical gravity center position of the load based on the detection output of the load sensor and the detection output of the tilt sensor, respectively.
The forklift according to claim 1. The computing means is configured to determine the vertical position of the load based on a detection output of the load sensor when the fork on which the load is placed is in each of a horizontal state and an inclined state and an inclination angle when the load is in the inclined state. Calculate the center of gravity position in the direction,
The forklift according to claim 1 or 2. Output means for outputting the data of the center of gravity calculated by the calculating means;
The forklift according to any one of claims 1 to 3. A gravity center position measuring device equipped in a forklift comprising a mast tilted in the front-rear direction and a fork supported so as to be movable up and down on the mast,
A fork attachment that is detachably attached to the fork and has at least two load sensors for detecting a load of a load placed on the fork and an inclination sensor for detecting an inclination angle of the fork;
Calculating means for calculating a horizontal gravity center position and a vertical gravity center position of the load based on the detection output of the load sensor and the detection output of the tilt sensor, respectively.
The center-of-gravity position measuring apparatus characterized by this.

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