JPH1095600A - Force control method for baggage carrying machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lift a baggage at a safe speed even if a force above a required value is input, by changing the flow of air supplied to a cylinder to control an up-moving speed when a speed above a required value is detected. SOLUTION: When a grip part 12b is lifted upward, the force whose direction is opposite to the gravity is transmitted to a force sensor 12a. The force sensor 12a converts the force into an electric signal and inputs it to a control substrate 14a of a control part 14 through a wire 15. A calculating part judges an up/ down moving status by a signal from a detector 17 and detects an up-moving speed not less than a desired speed and output it to a flow control valve 14c. The flow control valve 14c controls the movement of a cylinder by changing the flow of air supplied to the cylinder. When the grip part 12b is lowered in the direction of gravity, the calculating part judges the up/down moving status by the signal from the detector 17 and, when the speed is not less than a set down-moving speed, outputs a signal to the flow control valve 14c to change an air flow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cargo handling machine having a lifting / lowering mechanism such as a parallelogram link type or a jib type, which lifts and lowers cargo using an actuator such as an air cylinder or an electric motor. .

[0002]

2. Description of the Related Art In a cargo handling machine to which a conventional force control method is applied, a lifting force of the cargo handling machine is amplified by a human having an operation unit and the lifting force of the cargo handling machine is increased in accordance with a force for lifting the cargo. The cargo was raised and lowered by force.

[0003]

Here, the contents and problems of the conventional force control method described above will be described.
A control method that uses a force sensor provided in the operation unit to detect the lifting force when a person has the operation unit and tries to lift the cargo, and amplifies the lifting force to raise and lower the cargo. Insufficient safety features to regulate speed. In other words, if a person tries to move the cargo quickly, an excessive lifting force may be input, and the climbing speed is such that the person cannot follow the machine. In addition, when the cargo is being lifted, the force signal disappears when the person releases the operating part, and the cargo descends with a movement close to free fall, which may damage the cargo and harm humans. Was.

Further, if the machine reacts more excessively than the movement of a human, a phenomenon called hunting (repetition of unintentional lifting and lowering) occurs, and there is a problem that the vehicle cannot be operated as desired by the human. . At the same time, when the amplification degree of the force signal (F2 / F1: F1 is the lifting force of the person, F2 is the lifting force of the cargo handling machine) is large, and the load is lighter than the rated load, the lifting is performed. Skill was required to perform fine positioning with force.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and disadvantages. A mechanism for lifting and lowering cargo, a driving source for driving the lifting mechanism, and controlling the driving source are provided. Control unit and an operation unit for detecting the magnitude of the lifting force that is exerted when a person has the operation unit and tries to lift the cargo by means of a force sensor provided in the operation unit. In the cargo handling machine having a force control method of amplifying the lifting force of the cargo handling machine according to the lifting force and lifting and lowering the cargo with the lifting force and the lifting force, the lifting state is determined by the detector, and the lifting state is appropriately determined at the time of lifting. When a speed higher than desired is detected, the flow rate of air supplied to the cylinder is changed by a flow switching valve to control the rising speed, and a grip detector is provided in the operation unit, and a grip detector is provided. To determine the state By varying the air flow rate supplied to the cylinder at a flow rate switching valve, a force control method for handling product transporter, characterized in that to control the speed for raising and lowering the cargo handling thereof.

Next, an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a conceptual diagram of the embodiment. One end of an A-arm 4 is fixed to a fixed shaft 5 on a side plate of a main body 3 connected to a support 1 and a swivel 2, and the other end of the A-arm 4 is connected to a one end of a C-arm 7 via a support shaft 6. And link arm 8 and B
The arm 9 and the A-arm 4 and the C-arm 7 form a parallel link mechanism. In addition, a guide is provided for supporting the power point 10 of the parallel link mechanism in a direction perpendicular to the rotation axis of the swivel base 2, and the power point 10 of the parallel link is further moved by a cylinder 11 that can move up and down in parallel to the rotation axis of the swivel base 2. The operation unit 12 is provided with a force sensor 12a, a grip unit 12b, and a grip detector 18 at the other end of the C-arm 7. The operation unit 12 has a hook 13 for hanging a cargo 16. Further, regarding the control configuration, the control unit 14
Denotes a control board 14a, an electropneumatic proportional valve 14b, and a flow rate switching valve 1.
4C. The force sensor 12a and the grip detector 18 provided on the operation unit 12 and the detector 17 provided on the vertical stroke portion of the cylinder 11 input signals to the control board 14a. Further, the control board 14a is connected to the electropneumatic proportional valve 14b and the flow rate switching valve 14c.
4b is connected to the cylinder 11 via a flow switching valve 14C by an air pipe.

FIG. 2 is a block diagram of the control method. F1
Is a lifting force that is output when a human operates, and is input to the control board 14a of the control unit 14 via the electric wire 15,
After the arithmetic processing by the arithmetic unit, it is output to the electropneumatic proportional valve 14b, and the air proportional to the lifting force F1 is constantly supplied to the cylinder 11, so that the lifting force F2 is generated via the arm mechanism. . The control board 14a of the control unit 14 detects the vertical movement of the cylinder 11 with the detector 17, inputs a signal via the electric wire 17a, and determines the up / down state by the calculation unit. At the same time, a signal from the grip detector 18 disposed on the operation unit 12 is input to the calculation unit, and the flow rate of air supplied to the cylinder by the output from the calculation unit is varied by the flow switching valve 14c.

[0008]

From the above structure, the operation will be described with reference to FIG. 1. First, when the grip portion 12b is lifted upward, the force in the antigravity direction is transmitted to the force sensor 12a. The force sensor 12a converts the received force into an electric signal, is input to the control board 14a of the control unit 14 through the electric wire 15, and is subjected to integral amplification processing by the control board 14a.
Next, the ascending / descending state is determined by a signal from the detector 17 by an arithmetic unit, and an ascending speed that is higher than desired is detected and output to the flow switching valve 14c. The flow switching valve 14c controls the movement of the cylinder by changing the flow rate of air supplied to the cylinder. Further, by lowering the grip portion 12b in the direction of gravity, a signal from the detector 17 changes the up / down state to the control board 1.
When the speed is determined to be equal to or higher than the set descent value by the calculation unit 4a, the speed is output to the flow rate switching valve 14c and the air flow rate is varied, so that the normal up / down operation is performed.

When a person releases the operating unit, a signal from a grip detector 18 disposed on the operating unit 12
A is output to the control board 14a of the control unit 14 through a. The output signal is determined by the calculation unit and output to the flow switching valve 14c so that the flow switching valve 14c varies the air flow rate.
By controlling the falling speed, the impact of cargo on the floor is reduced.

When the amplification degree of the force signal (F2 / F1: F1 is the lifting force of a person and F2 is the lifting force of the cargo handling machine) is large, and when a load lighter than the rated load is transferred, When hunting occurs due to an excessive reaction of the movement of the machine rather than the movement of the hand, the grip detector 1 disposed on the operation unit 12
By releasing the hand from 8, the signal from the grip detector 18 is output to the control board 14a of the control unit 14 through the electric wire 18a. This output signal is discriminated by the calculation unit and the flow rate switching valve 14c
, The flow rate switching valve 14c varies the air flow rate and controls the speed of elevation. When fine positioning is performed by the lifting force, the vertical speed is controlled by varying the air flow rate by the flow rate switching valve 14c using the grip detector 18 in the same manner as described above.

[0011]

According to the above configuration and operation, the effect can be described. By using the control method according to the present invention in the conventional force control method, the force of a human hand to quickly lift a cargo can be moderated. Since the speed of the cargo handling machine does not reach a speed higher than desired without any problem, it is possible to lift the cargo at a safe speed even if an excessive lifting force is input. Also, even if a person releases the operating part under some circumstances while lifting the cargo, the cargo can safely descend without free falling and the impact of the cargo on the floor etc. This prevents damage and prevents harm to human feet due to cargo. Further, when the amplification degree of the force signal (F2 / F1: F1 is the lifting force of the person and F2 is the lifting force of the cargo handling machine) is large and the load is lighter than the rated load, the load of the person is reduced. Even when hunting occurs due to an excessive reaction of the machine rather than movement, the air flow rate can be varied by the flow switching valve to limit the ascending and descending speed, thereby preventing hunting. At the same time, fine positioning can be easily performed by the lifting force, and a great effect can be obtained on operability and safety that have not been achieved in the past.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an embodiment of the present invention.

FIG. 2 is a functional explanatory diagram (block diagram) of an embodiment of the present invention.

[Explanation of symbols]

1 support 2 swivel
3 Main unit 4 A arm 5 Fixed axis
6 Support shaft 7 C arm 8 Link arm
9 B arm 10 Power point 11 Cylinder 1
2 Operation unit 12a Force sensor 12b Grip unit 1
3 Hook 14 Control unit 14a Control board 1
4b Electro-pneumatic proportional valve 14c Flow rate switching valve 15 Electric wire 1
6 Cargo cargo 17 Detector 17a Electric wire 1
8 Gripping detector 18a Electric wire F1 Lifting force F2 Lifting force of cargo handling machine W Weight of cargo

Claims (2)

[Claims] An apparatus has a mechanism for lifting and lowering a cargo, a drive source for driving the lifting mechanism, a control unit and an operation unit for controlling the drive source, wherein a human has an operation unit and can handle the cargo. The magnitude of the lifting force in the anti-gravity direction that is issued when trying to lift is detected by a force sensor provided on the operation unit, and the lifting force of the cargo handling machine is amplified according to the magnitude of the lifting force, and In a cargo handling machine having a force control method of lifting and lowering cargo with lifting force and lifting force, the lifting state is determined by a detector, and when a speed more than desired is detected ascending, the air flow supplied to the cylinder is determined. A force control method for a cargo handling machine, wherein a rising speed is controlled by changing the flow rate with a flow switching valve. 2. A force control method for a cargo handling machine according to claim 1, wherein a grip detector is provided in the operation unit, a state is determined by the grip detector, and an air flow supplied to the cylinder is a flow rate switching valve. A force control method for a cargo handling machine, characterized in that the speed at which the cargo is lifted and lowered is controlled by making the variable.