JPH07478Y2 - Hydraulic equipment for cargo handling vehicles - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention supports a loading platform to be lifted up and down on a mast that is erected on a trolley, and lifts and lowers the luggage together with an operator.
The present invention relates to a hydraulic device for a cargo handling vehicle that carries and moves luggage together with an operator.

"Prior Art" Conventionally, a master cylinder for raising and lowering a loading platform, a hydraulic pump for operating the cylinder, an electric motor for driving the pump, and a hydraulic switching valve for controlling the operation of the cylinder are provided, and an elevation lever is used. There was a technology for switching the switching valve and lifting / lowering luggage.

[Problems to be Solved by the Invention] In the prior art, the lifting lever is directly connected to the spool of the hydraulic switching valve, the switching valve is switched by operating the lever, and the lifting speed of the loading platform is adjusted by controlling the lever. Therefore, only rough adjustments can be made, and it is difficult to obtain an appropriate lifting speed of the platform according to the working conditions, and there is a problem of lack of safety.

"Means for Solving Problems" However, the present invention, a master cylinder for raising and lowering the loading platform,
A hydraulic pump that operates the cylinder, an electric motor that drives the pump, a hydraulic switching valve that controls the operation of the cylinder, and an up-and-down speed adjusting electric motor that moves the spool of the switching valve forward and backward by a switching operation of an up-and-down lever,
A load, a height of a cargo bed, and sensors for detecting the inclination angle of the vehicle body, and in a cargo handling vehicle configured to automatically control the motor based on the detection values of the sensors, the detection values of the sensors and When any of the differences from this set value is greater than or equal to a predetermined value, the up-and-down speed adjusting electric motor is speed-up controlled, while any one of the differences between the detected value of each sensor and this set value is less than or equal to the predetermined value. At this time, the ascending / descending speed adjusting electric motor is configured to be decelerated.

[Operation] Therefore, according to the present invention, the adjustment of the ascending / descending speed of the loading platform can be automated, finer adjustment can be performed compared to the conventional one, and the loading platform can be lifted / lowered at an appropriate speed according to the working conditions. It is possible to easily improve safety, especially during automatic lifting, when the difference between the detected value of each sensor and this set value is within the safety allowable range, the loading platform can move at a high lifting speed. The smooth lifting and lowering of the loading platform can be performed at a slow lifting speed when the difference between the detected value and the set value is within the critical value, even if one of the differences is below the specified value. It aims to further improve both safety and safety.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings. First
The figure is a hydraulic circuit diagram of essential parts, FIG. 2 is an overall side view of the cargo handling vehicle, FIG. 3 is a rear view of the same, and FIG. 4 is a plan view of the same, in which (1) is a trolley base (2 ) Equipped with front left and right wheels (3) and (3), left and right rear wheels (4) and (4), and steering wheels (5), and (6) and (6) are the rear wheels (4) and (4). ) Each of which is driven by an electric motor for traveling with an electromagnetic brake,
(7) is a steering electric motor that drives the steering wheels (5) to rotate, (8) and (8) are fixed masts of telescopic masts that are erected on both sides of the rear part of the base (1), and (9). ) Is a loading platform for supporting the movable mast (10) (10) of the telescopic mast so as to be able to move up and down, (11) (11) is the fixed mast (8)
A handle for pushing and pulling, which is fixed to the back side of (8), (1
2) is a master cylinder which is erected on the base (1) between the movable side masts (10) and (10) via a base (13),
4) is the piston rod of the cylinder (12) whose tip is connected to the upper horizontal connecting frame (15) of the movable side mast (10) (10), and (16) (16) is the piston rod (1).
The load chain is stretched between the loading platform (9) and the upper horizontal connecting frame (18) of the stationary mast (8) via chain wheels (17) (17) pivotally supported on both sides of the tip of (4).

Further, a hydraulic pump (19) for operating the master cylinder (12) and a pump motor (20) which is an electric motor for driving the pump (19) are integrally connected to each other with an oil passage forming plate (21) interposed therebetween, and A hydraulic unit (23) forming an oil tank (22) is provided outside the pump (19), the hydraulic unit (23) is provided at the rear of the base (2), and the batteries (24) (24) are provided at the front. On the other hand, as shown in FIG. 5, the operator protection punches (25) (2
5) to form a driving operation part (26), and a steering handle (2
7), forward / reverse / stop selector switches (28) (2
9) (30), manual lifting lever (31), various indicator lamps (3
2) and the battery meter (33) and the like are arranged in the operation box (34) of the operation section (26), and the accelerator pedal (35) is provided on the upper surface of the loading platform (9) of the operation section (26). It is arranged to operate the cart (1) on the platform (9) and to move the platform (9) up and down to lift and lower the luggage together with the worker and carry the luggage together with the worker. Is configured.

In the figure, (36) is a boarding step that is foldably attached to one side of the luggage carrier (9), and (37) and (37) are luggage guards that are detachably attached to both front corners of the luggage carrier (9).

As shown in FIG. 1, a hydraulic switching valve (38) for connecting and controlling the master cylinder (12) to the hydraulic pump (19) and the oil tank (22) is formed on the plate (21), and one end of the plate is changed to the plate. A neutral check valve which is opened by the spool (40) against a spool (40) screwed into the (21) via a screw portion (39) and a spring (42) crimped and supported on the valve seat (41). (43) and a lowering check valve (47) which is opened against the spring (46) which is pressed and supported on the valve seat (45) via the push rod (44) by the opening operation of the check valve (43). , A switching valve (38), and an elevating / lowering switching motor (50) which is an ascending / descending speed adjusting electric motor connected to the other end of the spool (40) via bevel gears (48) (49). (50) Rotate and push the spool (40) More opens the neutral check valve (43), and configured to open further the spool (40) lowering check valve by pushing it by rotating the (47).

Further, a discharge check valve (51) for preventing backflow of pressure oil to the hydraulic pump (19) is provided in the plate (21), and the discharge check valve (51) is attached to the valve seat (52) by the spring (53). The check valve (51) is connected to the relief pump (54) in parallel with the hydraulic pump (19) in parallel with the check valve (51), and the hydraulic pump (19) is connected via the discharge check valve (51) and the neutral check valve (43). ) Is connected to the oil tank (22), the hydraulic pump (19) is connected to the master cylinder (12) via the discharge check valve (51) and the lowering check valve (47), and the lowering check valve (47) and The master cylinder (12) is connected to the oil tank (22) through the neutral check valve (43), and the spool (40) is moved back and forth by driving the motor (50), whereby the neutral check valve (43) and the downward check valve (43) are Four
7) is opened and closed as appropriate to switch the loading platform (9) between up and down, and the opening amounts of the neutral check valve (43) and down check valve (47) and valve seats (41) and (45) are adjusted. Then
It is configured to adjust the lifting speed of the loading platform (9).

In the figure, (55) is a plug that is screwed into the open end screw part (56) of the plate (21) to seal the part, and (57) is the lowering check valve (47) and the spring (46). A plug adapter that is internally provided to form the valve seat (45) is a hose joint that is screwed and fixed to the plug adapter (57) that is screwed and fixed to the open end screw portion (59) of the plate (21). .

As shown in FIG. 6, a switch operating piece (60) is provided on the elevating lever (31), and when the elevating lever (31) is raised, it is turned on through the operation valve (60) at the initial stage of the operation. A motor switch (61) and a potentiometer type lift lever sensor (62) for detecting the lever position of the lift lever (31) are attached to the operation box (34).

As shown in FIG. 7, a load raising / lowering control circuit (63) for manually and automatically controlling the pump motor (20) and the raising / lowering switching motor (50) is provided, and a manual / automatic switching of the circuit (63) is performed. Automatic changeover switch (64), potentiometer type load sensor (65), load setting device (66) for setting and inputting maximum load to the circuit (63), and loading platform (9)
Potentiometer type height sensor (67), height setting device (68) for setting and inputting the maximum and minimum heights of the loading platform (9) to the circuit (63), and detecting the left and right and front and rear inclination angles of the vehicle body Left and right potentiometer tilt angle sensor (69)
And a front and rear tilt angle sensor (70), a tilt angle setting device (71) for setting and inputting the maximum left, right, front and rear tilt angles of the vehicle body to the circuit (63), and rotation of the lifting motor (50) to detect spool. Spool sensor (72) that detects the forward / backward position of (40)
And the circuit (63) each switch (61) (64)
And each sensor (62) (65) (67) (69) (70) (72) and each setting device (66) (68) (71) and the battery (2
4) is connected to the input, and the lifting speed of the platform (9) is adjusted manually or automatically.

This embodiment is configured as described above, and when an operator gets on the driving operation part (26) of the loading platform (9) and switches the automatic / manual changeover switch (64) to the manual operation, the lifting operation is performed. When the lever (31) is set to the neutral position shown in FIG. 6, the spool (40) is rotated and pushed into a position where only the neutral check valve (43) of the hydraulic pressure switching valve (38) is opened, so that the elevator switching motor (50) is moved. ) Is controlled to stop the master cylinder (12), the motor switch (50) is turned off to stop the pump motor (20), and the hydraulic pump (19) is stopped.

When the raising / lowering lever (31) is switched from the neutral position shown in FIG. 6 to the lowering side, the motor switch (61) is held off and the pump motor (20) is stopped, and the hydraulic pump (1) is held.
9) is stopped and held, and with the neutral check valve (43) of the switching valve (38), the spool (40) is rotated and pushed into a position where the lowering check valve (47) is opened, so that the up / down switching motor ( 50) is operated and controlled, the pressure oil of the master cylinder (12) is returned to the oil tank (22) through the check valves (47) (43), and the loading platform (9) is lowered. Check valves (47) (43) and valve seats (45) (4) corresponding to the amount of downward movement of (31).
1) so as to obtain the amount of opening with
0) is controlled to adjust the lowering speed of the loading platform (9).

On the other hand, when the raising / lowering lever (31) is switched from the neutral position shown in FIG. 6 to the motor starting position on the rising side, the motor switch (61) is turned on via the switch operating piece (60) of the raising / lowering lever (31). Switch to start the pump motor (20),
Drive the hydraulic pump (19). At this time, the lifting / lowering switching motor (50) is operated and controlled so that the spool (40) is rotated and pushed into a position where only the neutral check valve (43) of the switching valve (38) is opened, and the pump motor (20). By releasing the pressure oil of the hydraulic pump (19) at startup to the oil tank (22) through the neutral check valve (43), the master cylinder (12) is temporarily prevented from rising rapidly, and the pump motor The shock caused by the change in the instantaneous activation force of (20) is prevented from acting on the platform (9) as a sudden rising force.

Further, when the raising / lowering lever (31) is switched from the motor starting position shown in FIG. 6 to the raising side, the motor switch (61)
Is turned on to keep the pump motor (20) driven, and the hydraulic pump (24) is driven to be held, and each check valve (51) (4
Pressure oil is made to flow into the master cylinder (12) via 7) to raise the platform (9). At this time, the neutral check valve (43) is in the open state, and the pressure oil discharged from the pump (19) is Part of the oil is returned to the oil tank (22). Then, the open / close switching motor (the opening / closing switching motor (31) is sequentially closed so that the neutral check valve (43) and the valve seat (41) are gradually closed according to the amount of operation of the lifting lever (31) to the up side. 50) is operated and controlled, and the amount of pressure oil sent to the master cylinder (12) is adjusted to adjust the rising speed of the bed (9).

On the other hand, by automatically switching the automatic / manual switch (64), the lifting speed of the loading platform (9) is automatically adjusted by adjusting the lifting lever (31), and this automatic adjustment is maximum. Load sensor (6) from load (A)
The output value (H) of 5) is small (A ≧ H), and the output value (I) of the height sensor (67) is smaller (B ≧ I) than the maximum height (B) of the loading platform (9), The output value (I) of the height sensor (67) is larger than the minimum height (C) of the loading platform (9) (C ≦ I), and the left and right of the vehicle body and the left and right maximum tilt angles (D) and (E) And when the output values (J) and (K) of the front and rear inclination angle sensors (69) and (70) are small (D ≧ J) (D ≧ K), they are first performed.

Then, when these conditions are satisfied, the position of the lift lever (31) is detected from the output value (F) of the lift lever sensor (65), and when the lift lever (31) is supported at the neutral position, the control is stopped. To be done.

Further, when the elevating lever (31) is operated to the descending operation end position or the ascending operation end position, the difference between the maximum load (A) and the output value (H) of the load sensor (65) is a certain value or more,
When the difference between the maximum height (B) and the minimum height (C) of the loading platform (9) and the output value (I) of the height sensor (67) is equal to or more than a certain value, the maximum inclination angle (D) of the vehicle body in the left-right and front-rear directions ) And (E) and the difference between the output values of the left and right and front and rear inclination angle sensors (69) and (70) is a certain value or more, the acceleration control is performed in proportion to the difference between the respective values, When any one of the differences becomes a certain value or less, deceleration control is performed in proportion to the difference between the respective values, and the loading platform (9) is moved up and down at a lifting speed of the loading platform (9) corresponding to the working condition. It is a thing.

During the automatic adjustment of the ascending / descending speed, the hydraulic pressure switching valve (38) is switched to the neutral / ascending / descending state in parallel with this automatic adjustment, and the acceleration / deceleration control maintains the ascending / descending switching state. It is done within that range.

[Advantages of the Invention] As is apparent from the above-described embodiments, the present invention includes a master cylinder (12) for moving the loading platform (9) up and down, and the cylinder (1).
Hydraulic pump (19) for operating 2) and this pump (1
9) electric motor (20) for driving the cylinder (1)
2) The hydraulic switching valve (38) that controls the operation, and the lifting lever (3
By the switching operation of 1), the spool (4) of the switching valve (38) is
Electric motor (50) for moving up and down (0) and each sensor (6) for detecting load, height of platform and tilt angle of vehicle body
5) (67) (69) (70) and each of the sensors (65)
(67) (69) (70) based on the detection value of the motor (5
In a cargo handling vehicle in which 9) is automatically controlled, when the difference between the detected value of each sensor (65) (67) (69) (70) and this set value is greater than or equal to a predetermined value While increasing the speed of the adjusting electric motor (50), each sensor (6
5) It is configured to control the speed-lowering electric motor (50) to decelerate when any one of the differences between the detected values of (67) (69) (70) and this set value is less than a predetermined value. , The lifting speed of the loading platform (9) can be automated, finer adjustments can be made than before, and the loading platform (9) can be raised and lowered at an appropriate speed according to the working conditions, thus improving work efficiency. Along with that, it is possible to easily improve safety,
Especially for automatic lifting, each sensor (65) (67) (69)
When the difference between the detected value of (70) and this set value is within the safety allowable range, which is equal to or greater than the predetermined value, the loading platform (9) can be smoothly lifted and lowered at a high lifting speed and detected. When any one of the difference between the value and the set value is within the dangerous range where the value is less than or equal to the predetermined value, the loading platform (9) can be safely lifted and lowered at a slow lifting speed, and work efficiency and safety can be improved. There is a remarkable effect that it can be further improved on both sides.

[Brief description of drawings]

1 is a hydraulic circuit diagram of essential parts, FIG. 2 is an overall side view of a cargo handling vehicle, FIG. 3 is a rear view thereof, FIG. 4 is a plan view thereof, FIG. 5 is a plan view of a cargo bed, and FIG. The figure is a side view of the lift lever.
FIG. 7 is a control circuit diagram, and FIG. 8 is a flowchart. (9) ... Load platform (12) ... Master cylinder (19) ... Hydraulic pump (20) ... Electric motor (38) ... Hydraulic switching valve (40) ... Spool (50) ... Elevating speed adjusting electric motor (65) ... Load sensor (67)… Height sensor (69)… Left and right tilt angle sensor (70)… Front and back tilt angle sensor

Continuation of front page (72) Koichi Ichihara, 263, Tangami Mikami-cho, Minamikawachi-gun, Osaka Prefecture, Ltd. Kudaya Giken Co., Ltd. (JP, B2)

Claims (1)

[Scope of utility model registration request] 1. A master cylinder (12) for raising and lowering a cargo bed (9), a hydraulic pump (19) for operating the cylinder (12), an electric motor (20) for driving the pump (19), and the cylinder. A hydraulic switching valve (38) for controlling the operation of (12), a lifting speed adjusting electric motor (50) for moving the spool (40) of the switching valve (38) forward and backward by a switching operation of the lifting lever (31), a load, It is equipped with each sensor (65) (67) (69) (70) that detects the height of the luggage carrier and the inclination angle of the vehicle body, and is based on the detection value of each sensor (65) (67) (69) (70). In the cargo handling vehicle in which the motor (50) is automatically controlled, the sensors (65) (67) (69)
When the difference between the detected value of (70) and the set value is greater than or equal to a predetermined value, the up / down speed adjusting electric motor (50) is speed-up controlled, while the sensors (65) (67) (69) ( The hydraulic system for a cargo handling vehicle, characterized in that the lifting speed adjusting electric motor (50) is decelerated when any one of the differences between the detection value of 70) and the set value is less than or equal to a predetermined value. .