JP2002362900A - Cargo carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cargo carrier capable of reducing total size thereof, simplifying motor control for reducing arm pressing force, and manufacturing at a low cost. SOLUTION: A motor 12 is used for an actuator. A brake 13 retaining load by making a disk and a lining always contact in lowering and stopping is used. Derricking of an arm 1 is controlled with the motor 12 and the brake 13. The load is retained by the brake 13 and a worm reduction gear 14. When the arm 1 gets into a state of pressing a cargo on a floor surface in lowering, a pressing detector 24 operates to stop signal for lowering of the motor 12. A computing part is provided to determine an abnormal state and send a lifting drive signal to the motor 12 to prevent quick drop when a braking function of the brake 13 deteriorates.

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 of a parallel link type or a jib type using a motor as an actuator.

[0002]

2. Description of the Related Art In order to control the lifting speed by a motor alone in a cargo handling machine, there is a method of using a motor such as a torque motor or a servomotor capable of obtaining a sufficient output at zero rotation. Further, for a motor such as an induction motor which cannot obtain a sufficient output at zero rotation, there is a method of holding a load by using an electromagnetic brake when the motor approaches zero rotation. However, there has been no configuration that uses a brake (hereinafter, referred to as a "slide brake") in which the disc and the lining are always in contact to hold the load. Further, when the arm is pressed against the floor surface or the cargo during lowering, there is a mechanism for preventing the arm from being pressed down as disclosed in Japanese Patent Application No. 7-346601.

[0003]

When a torque motor is used as an actuator for controlling the ascending and descending speed, the motor becomes large, and when a servo motor is used, the motor becomes small, but the control unit becomes complicated and expensive. Also, in a mechanism such as a servomotor that rotates in the normal and reverse directions to move up and down, an arm and a drive are configured to have a separated structure in order to reduce the pressing force as in the application of Japanese Patent Application No. 7-346601. However, it is necessary to always control the driving device and the lifting mechanism so as not to separate from each other, and the control unit becomes complicated. When the electromagnetic brake is used, when the electromagnetic brake is raised or lowered from a stop, or when the motor is stopped from a raise or a descent, the electromagnetic brake is excited and released, and lacks smoothness.

According to the present invention, when a motor which cannot obtain a sufficient output at zero rotation is used for a cargo handling machine, the load is held by using a sliding brake and a worm speed reducer, so that the motor descends due to the load when descending. The size of the slide brake is reduced as compared to holding the load with the slide brake alone, and the drive unit and the overall size can be reduced by controlling the motor's forward / reverse rotation to control the vertical speed. In addition, it performs control to smoothly transition from stop to ascending or descending, or from ascending or descending to stopping, and simplifies the control to reduce the pressing force. It is intended to provide.

[0005]

SUMMARY OF THE INVENTION In a cargo handling machine having a speed commander for instructing elevating, an elevating mechanism for raising and lowering an arm, and a driving device for driving the elevating mechanism, a motor is used as an actuator, and a motor is used for lowering. Also, at the time of stop, a brake and a worm speed reducer that keep the load by contacting the disk and the lining are always used, and the motor and the brake control the elevation of the arm.

[0006] The lifting plate is pivotally mounted via a support shaft provided on the driving device, and a pressing detector is provided on the lifting plate, and the arm is pressed against the floor surface or cargo when the vehicle descends. When the state is reached, the pressing detector operates to stop the signal of the lowering of the motor, and the elevating plate moves about the support shaft.

When the braking function of the brake is reduced, an abnormal state is determined based on a speed signal of a speed detector provided in the motor and a command signal of a speed commander, and an ascending drive signal is sent to the motor to suddenly stop. It has a calculation unit to prevent the descent.

[0008]

FIG. 1 is a general view of an embodiment. FIG. 2 is an enlarged view of the lifting plate and the driving device of FIG. FIG.
Will be described with reference to FIG. The arm 1 is a parallelogram-shaped link mechanism, and is an elevating mechanism 2 that is parallel to the horizontal and turning directions. At the tip of the arm 1, a speed command device 3 for instructing lifting and lowering is disposed, and also holds a cargo 4. The swivel base 5 is supported on a main body plate 6. The swivel 5 is fixed to the pole / pedestal 7. The pole / pedestal 7 includes a rechargeable battery 8 and casters 9
And a hand push bar 10 so that the user can move to a place where there is no power supply and work. The driving device 11 includes a motor 12, a sliding brake 13, a worm speed reducer 14, a pinion gear 15, a rack 16, and a speed detector 17. The worm speed reducer 14 is engaged with the motor 12, and the driving force of the motor 12 is transmitted. The motor 12 engages the slide brake 13 and the speed detector 17. The pinion gear 15 is engaged with the worm speed reducer 14, and the rotation of the worm speed reducer 14 is transmitted. The rack 16 is engaged with the pinion gear 15. A rail 18 is provided on the main body plate 6. An elevating plate 20 is attached to the main body plate 6 via a support shaft 19 provided on the rack 16.
Is provided, and the driving force from the driving device 11 is transmitted to the arm 1 via the elevating plate 20 to move the arm 1 up and down. Thus, the cargo handling machine 21 can transport the cargo 4 three-dimensionally. When stopped, the sliding brake 13 and the worm reducer 14
The load is held by the braking effect. When the motor 12 rotates in the ascending direction, when the motor 12 rotates in the ascending direction, the sliding brake 13 is released by the rotation, and the driving force of the motor 12 is transmitted through the worm speed reducer 14, the pinion gear 15, the rack 16, the supporting shaft 19, and the elevating plate 20. And the arm 1 is raised. When the motor 12 rotates in the descending direction, the load is held by the sliding brake 13 and the worm speed reducer 14, and when the motor 12 rotates in the descending direction, the slip brake 13 is always in a slipping state.
5. The arm 1 is transmitted to the arm 1 via the rack 16, the support shaft 19, and the elevating plate 20, and the arm 1 descends. Drive unit 1
Although the worm speed reducer 14, the pinion gear 15, and the rack 16 are examples of the means for transmitting the driving force 1 to the lifting mechanism 2, a planetary speed reducer or a harmonic speed reducer and a ball screw may be used. The power supply is equipped with a rechargeable battery 8 mounted on the pole / pedestal 7.
It may be taken from the C power supply.

FIGS. 2, 3 and 4 are enlarged views of the lifting plate and the driving device of FIG. FIG. 2 shows a normal lifting state, FIG. 3 shows a state in which the arm is pressed against the floor or cargo when the arm is lowered, and FIG. 4 shows a state in which the arm is pressed against the floor or cargo when the arm is further lowered from the state shown in FIG. This is the case. FIG. 5 is an enlarged view of a power point, a horizontal rail, a detection plate, and a pressing detector. 5A shows a normal ascending and descending state, and FIGS. 5B and 5D show a state in which the arm presses against the floor surface or cargo when the arm is lowered.
FIG. 5C shows a case where the arm is pressed against the floor or the cargo when the arm is further lowered from the state shown in FIG. 5B. This will be described with reference to FIGS. 2, 3, 4, and 5. The drive unit 11 includes a speed detector 17, a sliding brake 13, a motor 12, a worm reducer 14, a pinion gear 15, and a rack 16. The motor 12 is engaged with the sliding brake 13, the worm speed reducer 14 and the speed detector 17. The pinion gear 15 is engaged with the worm speed reducer 14, and the rotation of the worm speed reducer 14 is transmitted. A rail 18 is provided on the main body plate 6. An elevating plate 20 is pivotally mounted on the rack 16 via a support shaft 19. The rack 16 is engaged with the pinion gear 15,
As the pinion gear 15 rotates, the pinion gear 15 moves up and down together with the elevating plate 20, and the driving force of the motor 12 is transmitted. The elevating plate 20 is provided with a horizontal rail 22, a detecting plate 23, a pressing detector 24.25 and a roller 26. In a normal elevating state, the power point 27 of the arm 1 is in contact with the horizontal rail 22 fixed to the elevating plate 20 as shown in FIGS. When the arm 1 is pressed against the floor surface or the cargo 4 when the arm 1 is lowered, the rack 16 moves further downward and the power point 27 moves away from the horizontal rail 22 so that the power point 27 of the arm 1 is detected by the detection plate. 23 is pushed up, and as shown in FIGS. 3 and 5B, the switch of the pressing detector 24 is pressed. Pressing detector 2
When the switch 4 is pressed, the signal for lowering the motor 12 is switched to a stop signal. Even when the descending signal is switched to the stop signal, the rack 16 may slightly descend due to the descending speed. In this case, since the elevating plate 20 is pivotally mounted on the support shaft 19, FIGS. As shown in FIG. 5C, the elevating plate 20 moves upward around the support shaft 19, and the roller 26 is separated from the rail 18. Since the lifting plate 20 is pivotally mounted on the support shaft 19, only the weight of the arm 1, the speed commander 3, and the cargo 4 is pressed against the floor surface. Also, the cargo 1 has an arm 1
Only the own weight of the speed commander 3 and the cargo 4 is pressed. FIG. 5D shows a state in which the force point 27 pushes up the detection plate 23 on the pressing detector 25 side, and only the pressing detector 25 is operating. Power point 27
, The pressing detector 24 and the pressing detector 25
Both may operate.

FIG. 6 is another embodiment of an enlarged view of the lifting plate and the driving device of FIG. FIG. 6 shows a normal elevating state. The driving device 28 includes a speed detector 29 and a motor 30
And a worm speed reducer 31, a sliding brake 32, a pinion gear 33, and a rack 34. The motor 30 engages the speed detector 29 and the worm speed reducer 31. The worm speed reducer 31 has a sliding brake 32 engaged. The sliding brake 32 is engaged with a pinion gear 33. A rail 18 is provided on the main body plate 6. The elevating plate 20 is pivotally mounted on the rack 34 via the support shaft 19. The rack 34 is a pinion gear 33
To move up and down together with the lift plate 20 by the rotation of the pinion gear 33, and the driving force of the motor 30 is transmitted. The elevating plate 20 includes a horizontal rail 22, a detection plate 23, a pressing detector 24.25, and a roller 26.
Are arranged. In a normal elevating state, the horizontal rail 22 fixed to the elevating plate 20 has a power point 27 of the arm 1.
Is in contact.

FIG. 7 is a block diagram showing the operation unit. When the operator raises / lowers from the speed commander 3, a command signal 35 is sent to the speed calculation unit 36, the elevation determination unit 37, and the brake abnormality determination unit 38 according to the magnitude. The speed command calculation unit 36 calculates a command signal 35 from the speed command device 3 and a speed signal 39 from the speed detector 17 that detects the speed of the motor 12 so that the motor 12 rotates according to the command signal 35, The result is sent to the rotation direction switching unit 41 as a command speed signal 40. The elevating / decreasing determination unit 37 determines whether the command signal 35 has risen or descends, and sends an elevating signal 42 to the rotation direction switching unit 41. The rotation direction switching unit 41 switches the rotation direction of the motor 12 to the ascending or descending direction according to the elevating signal 42 from the elevating / deciding unit 37,
Command speed signal 40 from the motor 1
2, the motor 12 rotates in the ascending direction or the descending direction. The brake abnormality judging section 38 controls the speed command device 3
Signal 35 from speed sensor 3 and speed signal 3 from speed detector 17
9, when it is larger than the difference between the normal signals, it is determined that the brake holding force of the sliding brake 13 and the worm speed reducer 14 has decreased, and the brake abnormality determination signal 4
4 is output. Upon receiving the brake abnormality determination signal 44, the lifting / lowering determining unit 37 outputs a signal of a lifting command regardless of which signal is being output. This increase command is output until the speed signal 39 from the speed detector 17 becomes a stop signal and the brake abnormality determination signal 44 from the brake abnormality determination unit 38 is no longer output. As a result, it descends slowly due to the braking effect of the worm speed reducer 14, thereby preventing a sudden fall. On the other hand, FIG. FIG. FIG. 5 (b). FIG. 5 (c). FIG.
When the pressing detector 24.25 operates as shown in (d), a pressing signal 45 is sent from the pressing detector 24.25 to the speed command calculation unit 36, and the speed command calculation unit 36 sends the motor to the rotation direction switching unit 41. A command speed signal 40 for stopping the motor 12 is sent, and the rotation direction
Is sent to the motor 12, and the motor 12 stops. In the embodiment, the speed command device 3, the speed / speed detector 17, and the speed command calculation unit 36 are used. However, a position command device, a position detector, and a position command calculation unit may be used.

[0012]

According to the present invention, when a motor that does not provide sufficient output at zero rotation is used for a cargo handling machine, the load is held by using a sliding brake and a worm reducer so that the motor moves in the descending direction by the load when descending. It is possible to reduce the size of the slide brake as compared with holding the applied load with the slide brake alone, and also to reduce the size of the drive unit and the whole by controlling the motor forward and reverse to control the vertical speed,
In addition, it is possible to perform control to smoothly shift from stop to ascending or descending, or from ascending or descending to stopping, and to simplify the control to reduce the pressing force, to provide an inexpensive and safe cargo handling machine with good operability. There is a great effect that it can be manufactured.

[Brief description of the drawings]

FIG. 1 is a general view of an embodiment.

FIG. 2 is an enlarged view of a lifting plate and a driving device of FIG. 1;

FIG. 3 is an enlarged view of a lifting plate and a driving device of FIG. 1;

FIG. 4 is an enlarged view of a lifting plate and a driving device of FIG. 1;

FIG. 5 is an enlarged view of a power point and a horizontal rail, a detection plate, and a pressing detector.

FIG. 6 is another embodiment of an enlarged view of the lifting plate and the driving device of FIG. 2;

FIG. 7 is a block diagram illustrating a calculation unit.

[Explanation of symbols]

 Reference Signs List 1 arm 2 elevating mechanism 3 speed commander 12 motor 13 sliding brake 14 worm reducer 15 pinion gear 16 rack 17 speed detector 18 upper and lower plate 19 support shaft 20 elevating plate 24 pressing detector 25 pressing detector 38 brake abnormality determining unit 43 Drive signal 44 Abnormality judgment signal

Claims (4)

[Claims] 1. A cargo handling machine having a speed commander for instructing elevating, an elevating mechanism for elevating and lowering an arm, and a drive device for driving the elevating mechanism. A cargo handling machine characterized by using a brake that contacts a disk and a lining to hold a load, and controls lifting and lowering of the arm by the motor and the brake. 2. The lifting plate is pivotally mounted via a support shaft provided on the driving device, and a pressing detector is provided on the lifting plate. 2. The cargo handling machine according to claim 1, wherein the pressing detector is actuated to stop the signal for lowering the motor when the pressing plate is pressed against the supporting member, and the lifting plate moves about the support shaft. . 3. The cargo handling machine according to claim 1, wherein the load is held by the brake and the worm speed reducer. 4. When the brake function of the brake is reduced, an abnormal state is determined based on a speed signal of a speed detector provided in the motor and a command signal of a speed commander, and an ascending drive signal is sent to the motor. The cargo handling machine according to claim 1, further comprising a calculation unit that prevents sudden drop of the feed.