WO2021044526A1

WO2021044526A1 - Multiple valve device and cargo handling device equipped with multiple valve device

Info

Publication number: WO2021044526A1
Application number: PCT/JP2019/034646
Authority: WO
Inventors: 雅文垣尾
Original assignee: 株式会社島津製作所
Priority date: 2019-09-03
Filing date: 2019-09-03
Publication date: 2021-03-11
Also published as: JP7248131B2; JPWO2021044526A1

Abstract

Provided are a multiple valve device that enables the discovery of contaminants mixed into a working fluid, and a cargo handling device equipped with this multiple valve device. The multiple valve device (10) is provided with: a priority flow dividing valve (12) for dividing a working fluid into a priority flow and an excess flow and discharging the divided flows; a first line (L1) in which the priority flow flows; a second line (L2) in which the excess flow flows; a throttle unit (20) provided on the first line (L1) and/or the second line (L2); a first pressure gauge (22) for measuring the pressure of the working fluid on the upstream side of the throttle unit (20) in the first line (L1) and the second line (L2); and a control unit (26) for determining, from the pressure value of the first pressure gauge (22), that a contaminant has mixed into the working fluid.

Description

Multi-valve device and cargo handling device equipped with the multi-valve device

The present invention relates to a multiple valve device and a cargo handling device including the multiple valve device.

Conventionally, cargo handling devices such as forklifts that perform cargo handling work are equipped with multiple valve devices. The multiple valve device used in the forklift is connected to the cylinder that operates the steering wheel and fork, and the multiple valve device switches the supply amount of the hydraulic fluid (hydraulic oil) to each device.

Cargo handling equipment is often used in factories and warehouses. Foreign matter such as metal powder and paper powder may be mixed in the working fluid of the multiple valve device. If the amount of foreign matter mixed in the hydraulic fluid of the multiple valve device increases, or if a large foreign substance is mixed in, an abnormality may occur in the multiple valve device and the cargo handling device may stop. Therefore, it is important to detect an abnormality in the multiple valve device at an early stage.

International publication number WO2018 / 011999

For example, Patent Document 1 discloses a system for remotely detecting an abnormality in a vehicle. However, Patent Document 1 does not detect foreign matter mixed in the working fluid of the multiple valve device. In Patent Document 1, the cargo handling device may stop due to a foreign substance mixed in the working fluid of the multiple valve device.

An object of the present invention is to provide a multi-valve device capable of detecting foreign matter mixed in a working fluid and a cargo handling device including the multi-valve device.

In order to solve the above problems, the multiple valve device and the cargo handling device according to the present invention have the following configurations.

One aspect of the multiple valve device according to the present invention is a priority diversion valve that divides and discharges the hydraulic fluid into a preferential flow and a surplus flow, a first line through which the preferential flow flows, and a second line through which the surplus flow flows. And a throttle portion provided on at least one of the first line and the second line, and a first pressure gauge for measuring the pressure of the hydraulic fluid on the upstream side of the throttle portion in the first line and the second line. A control unit for determining whether foreign matter is mixed in the working fluid from the pressure value of the first pressure gauge is provided.

According to the present invention, when a throttle portion is provided and a foreign matter is caught in the throttle portion, the pressure difference between the upstream and the downstream of the throttle portion becomes large, so that the foreign matter is contained in the hydraulic oil. I can judge. Unlike the conventional method, foreign matter in the hydraulic oil can be detected. Since the abnormality can be detected and resolved at an early stage, it is less likely that the cargo handling device will be stopped.

It is a figure which shows the structure of the multiple valve apparatus of this application. It is a figure which shows the cargo handling apparatus. It is a figure of the diaphragm part which narrowed the diameter of the 2nd line. It is a figure of the diaphragm part which provided the plate body in the 2nd line. It is a figure which shows the multiple valve apparatus which provided the throttle part in the 2nd line. It is a figure which shows the multiple valve apparatus which provided the throttle part in the 1st line and the 2nd line. It is a figure which shows the multiple valve apparatus which omitted the 2nd pressure gauge. It is a figure which shows the multiple valve apparatus provided with a communication part.

The multiple valve device and the cargo handling device according to the embodiment of the present invention will be described with reference to the drawings. Although a plurality of embodiments will be described, the same means may be designated by the same reference numerals and the description thereof may be omitted even in different embodiments.

[Embodiment 1]
In the multiple valve device 10 shown in FIG. 1, the priority diversion valve 12 and the

directional control valves

14 and 16 are integrated. A plurality of

directional control valves

14 and 16 are provided, but the number of

directional control valves

14 and 16 is not limited. For example, when the multiple valve device 10 is used for the forklift (load handling device) 18 shown in FIG. 2, the

directional control valves

14 and 16 supply and discharge the hydraulic fluid (hydraulic oil) to the lift cylinder LS and the tilt cylinder TS. And switch between stop and stop. Depending on the configuration of the forklift 18, the number of

directional control valves

14 and 16 may be changed, or the internal configuration of the

directional control valves

14 and 16 may be changed.

The multiple valve device 10 measures the pressure on the upstream side of the throttle portion 20 in the priority flow valve 12, the first line L1, the second line L2, the first line L1, and the throttle portion 20 in the first line L1. It includes a first pressure gauge 22, a second pressure gauge 24 that measures the pressure on the downstream side of the throttle unit 20 in the first line L1, and a control unit 26 that determines an abnormality. In FIG. 1, reference numeral P is a port serving as an introduction port for the hydraulic fluid (hydraulic oil) discharged from the pump, and reference numeral T is a port serving as a discharge port to a tank for storing the hydraulic fluid.

[Priority diversion valve]
The input side of the priority shunt valve 12 is connected to the port P, and the output side is connected to the first line L1 and the second line L2. The hydraulic fluid sent from the pump is divided into a priority flow and a surplus flow by the priority distribution valve 12 and discharged. The priority shunt valve 12 is combined with the steering valve at the bottom of the steering 28, and is usually in the state shown in FIG. 1 by an internal spring, and the priority flow port is connected to the first line L1. .. When the steering 28 is being operated, the priority shunt valve 12 is in the state shown in FIG. 1, the priority flow port is connected to the first line L1, and the surplus flow port is connected to the second line L2. The priority flow flows through the first line L1 and the surplus flow flows through the second line L2. If the levers LL and TL are operated without operating the steering 28, the state of the priority shunt valve 12 is switched from the state shown in FIG. 1, and the flow rate of the hydraulic fluid on the second line L2 increases. In this case, the flow rate of the working fluid flowing through the first line L1 is smaller than that in FIG.

[1st line]
The first line L1 is a flow path of the hydraulic fluid to the steering 28 of the forklift 18. The first line L1 is connected to the port PF connected to the steering wheel 28. When the steering is being operated, the priority flow flows through the steering 28. Of the driving work and cargo handling work of the forklift 18, giving priority to the driving work leads to accident prevention.

[Second line]
The second line L2 is a flow path of the hydraulic fluid to the

directional control valves

14 and 16. The second line L2 is connected to the port T via the

directional control valves

14 and 16. The

directional control valves

14 and 16 are valves for controlling the working device of the forklift 18, and include a directional control valve 14 for moving the fork NL up and down and a directional control valve 16 for changing the angle of the mast MT. The

directional control valves

14 and 16 are operated by the levers LL and TL of the forklift 18. When the lever LL is operated, the directional control valve 14 is operated. The directional control valve 14 can control the flow to the port A1 connected to the lift cylinder LS. The port X is not used, and the directional control valve 14 prevents the hydraulic fluid from flowing to the port X. When the lever TL is operated, the directional control valve 16 is operated. The directional control valve 16 can control the flow to the ports A2 and A3 connected to the tilt cylinder TS.

Since the hydraulic fluid is preferentially supplied to the first line L1 by the priority shunt valve 12, when the steering operation is performed, the hydraulic fluid is preferentially diverted from the total amount of the hydraulic fluid supplied to the priority shunt valve 12 to the second line L2. The amount after deducting (surplus flow) flows. If the levers LL and TL are operated while the steering operation is stopped, the flow rate of the hydraulic fluid to the first line L1 is reduced, so that the flow rate of the hydraulic fluid to the second line L2 increases, and each cylinder LS, The movement of the TS becomes faster, and the movement of the fork NL and the mast MT becomes faster.

[Aperture section]
A throttle portion 20 is provided between the priority shunt valve 12 of the first line L1 and the port PF. The throttle portion 20 reduces the flow rate of the working fluid. A throttle valve is used for the throttle portion 20. By adjusting the opening and closing degree of the throttle valve, the flow rate of the hydraulic fluid is reduced. If no foreign matter is mixed in the working fluid, the pressure difference between the upstream and downstream of the throttle portion 20 falls within a certain range. When foreign matter enters the hydraulic fluid and is caught in the throttle portion 20, the pressure upstream of the throttle portion 20 increases and the pressure downstream of the throttle portion 20 decreases. If the pressure difference between the upstream and the downstream of the throttle portion 20 becomes larger than a certain range, it can be seen that foreign matter is caught in the throttle portion 20.

The throttle portion 20 is not limited to the throttle valve as long as the flow rate of the working fluid can be reduced. For example, as shown in FIG. 3, the diameter of the first line L1 may be narrowed to form the throttle portion 20, or as shown in FIG. 4, a plate body 30 provided in the first line L1 may be narrowed in diameter to form the throttle portion 20. It may be 20.

[Pressure gauge]
The pressure of the hydraulic fluid upstream of the throttle portion 20 in the first line L1 is measured by the first pressure gauge 22. The upstream of the throttle portion 20 is on the priority distribution valve 12 side of the throttle portion 20 in the first line L1. The pressure of the working fluid downstream of the throttle portion 20 in the first line L1 is measured by the second pressure gauge 24. The downstream side of the throttle portion 20 is on the port PF side of the throttle portion 20 in the first line L1. The first pressure gauge 22 and the second pressure gauge 24 can use a Bourdon tube pressure gauge, a diaphragm type pressure gauge, or the like, but the first pressure gauge 22 and the second pressure gauge 24 are not particularly limited as long as the pressure of the hydraulic oil can be measured.

[Control unit]
The pressure value of the first pressure gauge 22 and the pressure value of the second pressure gauge 24 are input to the control unit 26, and the control unit 26 determines that foreign matter is mixed in the working fluid using these pressure values. The control unit 26 uses a small computer such as an IC. The computer mounted on the forklift 18 may be used as the control unit 26. The control unit 26 takes the difference between the pressure values measured by the first pressure gauge 22 and the second pressure gauge 24, and if the difference is within the above-mentioned certain range, there is no abnormality in the working fluid, and if the difference exceeds the certain range, the working fluid is normal. It is judged that there is an abnormality (mixture of foreign matter) in.

When the control unit 26 determines that there is an abnormality in the hydraulic oil, it is preferable to display it at an arbitrary place on the forklift 18 or output a voice. Notify the operator of the forklift 18 of the abnormality.

[Other]
A third line L3 is provided in parallel with the second line L2. The third line L3 is connected to the first line L1 and the second line L2 via

pressure control valves

32 and 34. In the first line L1 and the second line L2, when the pressure of the hydraulic fluid in the lines L1 and L2 exceeds a certain level, the

pressure control valves

32 and 34 are opened and the hydraulic fluid is flowed to the third line L3. The pressure of the working fluids of the first line L1 and the second line L2 falls below a certain value. A throttle valve 36 may be provided between the priority shunt valve 12 and the pressure control valve 32 to adjust the flow rate of the hydraulic fluid to the pressure control valve 32.

[Abnormality judgment method]
When the steering 28 is operated, the priority flow valve 12 causes the priority flow of the hydraulic fluid to flow to the first line L1 and the excess flow to the second line L2. The pressure of the hydraulic fluid upstream of the throttle portion 20 is measured by the first pressure gauge 22, and the pressure of the hydraulic fluid downstream of the throttle portion 20 is measured by the second pressure gauge 24. If the difference between the measured pressure values is within a certain range, the control unit 26 determines that no foreign matter is mixed in the multiple valve device 10. If the difference between the measured pressure values becomes larger than a certain range, the control unit 26 determines that foreign matter is mixed in the multiple valve device 10. Replace the hydraulic fluid at an early stage so that the forklift 18 does not stop abnormally.

As described above, in the present application, by providing the throttle portion 20 in the first line L1 in which the hydraulic fluid is preferentially flowing, the pressure difference between the upstream and the downstream of the throttle portion 20 is increased when a foreign substance is caught in the throttle portion 20. It can be determined that foreign matter is contained in the hydraulic oil by using the increase in size. Unlike the conventional method, foreign matter in the hydraulic oil can be detected. Since the abnormality can be detected and resolved at an early stage, the forklift 18 is less likely to be stopped. The throttle portion 20 does not stop the flow of the hydraulic fluid to the steering 28 and does not affect the steering operation.

[Embodiment 2]
As in the multiple valve device 50 of FIG. 5, the throttle portion 20, the first pressure gauge 22, and the second pressure gauge 24 may be provided on the second line L2. A throttle portion 20 is provided between the priority diversion valve 12 and the directional control valve 14 in the second line L2. The first pressure gauge 22 measures the pressure of the hydraulic fluid upstream of the throttle portion 20 in the second line L2, and the second pressure gauge 24 measures the pressure of the hydraulic fluid downstream of the throttle portion 20 in the second line L2. The control unit 26 determines an abnormality by using the difference between the pressure values measured by the first pressure gauge 22 and the second pressure gauge 24 as in the above embodiment.

As in the multiple valve device 60 of FIG. 6, throttle portions 20 are provided in both the first line L1 and the second line L2, and the pressures of the hydraulic oils upstream and downstream of each are the pressure gauges 22 and the second. It may be measured by the pressure gauge 24. An abnormality is determined by using the pressure difference between the upstream and downstream of the throttle portion 20 of each line L1 and L2. Since the number of diaphragms 20 is increased, it is easy to detect an abnormality.

[Embodiment 3]
As in the multiple valve device 70 of FIG. 7, foreign matter may be detected using only the first pressure gauge 22. In this case, the control unit 26 obtains information on the steering wheel 28 from the steering control device 72 that controls the steering wheel 28. The information on the steering 28 includes the angle of the steering 28. The pressure of the hydraulic fluid downstream of the throttle portion 20 can be known from the angle of the steering 28. The control unit 26 stores the pressure downstream of the throttle unit 20 according to the angle of the steering 28 in a storage unit (not shown). The control unit 26 determines an abnormality by taking the difference between the pressure obtained from the first pressure gauge 22 and the pressure according to the angle of the steering wheel 28.

[Embodiment 4]
As shown in FIG. 8, the multi-valve device 80 provided with the communication unit 82 may be used. The pressure value acquired by the control unit 26 is transmitted to the host computer 86 via the network 84. Examples of the communication unit 82 include a device capable of performing mobile communication via the network 84, a device for wireless communication such as WiFi, and the like. The measured value is transmitted by the communication unit 82 and stored in the storage means of the host computer 86. Further, the host computer 86 may determine the abnormality performed by the control unit 26. The result determined by the host computer 86 may be displayed by the forklift 18 used by the operator via the network 84. The

multiple valve devices

50, 60, and 70 of FIGS. 5 to 7 may also have a configuration in which the communication unit 82, the network 84, and the host computer 86 are provided as in FIG.

[Embodiment 5]
The multiple valve device may be variously changed depending on the configuration of the forklift 18, and is not limited to the multiple valve device of the above-described embodiment. For example, the number of

directional control valves

14 and 16 may be three or more. For example, if a cylinder for moving the fork NL to the left or right is provided, a directional control valve for supplying the hydraulic fluid to the cylinder is added.

Although the forklift 18 has been described as the cargo handling device, the cargo handling device is not limited to the forklift 18 as long as the multiple valve device described above is used.

(Clause 1) In the multiple valve device of the present application, a priority diversion valve that divides and discharges the hydraulic fluid into a priority flow and a surplus flow, a first line through which the priority flow flows, and a second line through which the surplus flow flows. And a throttle portion provided on at least one of the first line and the second line, and a first pressure gauge for measuring the pressure of the hydraulic fluid on the upstream side of the throttle portion in the first line and the second line. A control unit for determining whether foreign matter is mixed in the working fluid from the pressure value of the first pressure gauge is provided.

According to the multiple valve device described in item 1, the pressure value of the first pressure gauge rises due to foreign matter being caught in the throttle portion, and the control unit can determine an abnormality. It is possible to determine an abnormality in the hydraulic circuit, which was not possible in the past, and prevent the cargo handling device from stopping.

(Item 2) In the first line and the second line, a second pressure gauge for measuring the pressure of the hydraulic fluid on the downstream side of the throttle portion is provided, and the control unit has a pressure value of the first pressure gauge and a second. Judge that foreign matter is mixed in the working fluid from the pressure value of the pressure gauge.

According to the multiple valve device described in the second item, an abnormality can be determined by utilizing the fact that the pressure difference between the hydraulic fluid upstream and downstream of the throttle portion becomes large due to foreign matter being caught in the throttle portion.

(Item 3) When the difference between the pressure value of the first pressure gauge and the pressure value of the second pressure gauge becomes larger than a certain range, the control unit determines that foreign matter is mixed in the working fluid. ..

According to the multi-valve device described in the third item, as the amount of foreign matter in the working fluid increases, the difference in pressure value gradually increases. The continuous valve device can be repaired.

(Section 4) The cargo handling device of the present application includes the multiple valve device described in paragraphs 1 to 3.

Since the cargo handling device described in paragraph 4 uses the above-mentioned multiple valve device, the stop of the multiple valve device can be prevented, so that the stop of the cargo handling device can be prevented.

In addition, the present invention can be carried out in a mode in which various improvements, modifications and changes are made based on the knowledge of those skilled in the art without departing from the gist thereof.

10, 50, 60, 70, 80: Multiple valve device 12: Priority diversion valve 14, 16: Direction control valve 18: Forklift (cargo handling device)
20: Squeezing unit 22, 24: Pressure gauge 26: Control unit 28: Steering 30: Plate 32, 34: Pressure control valve 36: Squeezing valve 72: Steering control device 82: Communication unit 84: Network 86: Host computer PF, X, A1, A2, A3, P, T: Port L1, L2, L3: Line LL, TL: Lever LS, TS: Cylinder NF: Fork MT: Mast

Claims

A priority divergence valve that divides the hydraulic fluid into a priority flow and a surplus flow and discharges them.
The first line through which the priority flow flows and
The second line through which the excess flow flows and
A diaphragm portion provided on at least one of the first line and the second line, and
In the first line and the second line, a first pressure gauge for measuring the pressure of the hydraulic fluid on the upstream side of the throttle portion, and a first pressure gauge.
A control unit that determines from the pressure value of the first pressure gauge that foreign matter is mixed in the working fluid, and
Multi-valve device with.
In the first line and the second line, a second pressure gauge for measuring the pressure of the hydraulic fluid on the downstream side of the throttle portion is provided.
The multiple valve device according to claim 1, wherein the control unit determines from the pressure value of the first pressure gauge and the pressure value of the second pressure gauge that foreign matter is mixed in the working fluid.
When the difference between the pressure value of the first pressure gauge and the pressure value of the second pressure gauge becomes larger than a certain range, the control unit determines that foreign matter is mixed in the working fluid. Ream valve device.
A cargo handling device including the multiple valve device according to claim 3.