GB2501762A

GB2501762A - An electric control module for a hydraulic coupler

Info

Publication number: GB2501762A
Application number: GB1207871.3A
Authority: GB
Inventors: Andrew John Harker; Douglas David Guest
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-05-04
Filing date: 2012-05-04
Publication date: 2013-11-06
Also published as: GB201207871D0

Abstract

An electronic control module 9 for activating a valve 10 of a hydraulic coupler comprises a two button fail safe sequential operation to avoid accidental operation of the valve. The valve acts as a lock to prevent operation of the hydraulics 12 on the coupler to detach or attach an accessory. The module comprises a pre-programmed printed circuit board with a self diagnostic fault detection system allowing the coupler to be locked when a fault is detected. The module is preferably a self contained waterproof box. The system preferably includes a two-tone warning system and a two colour warning display.

Description

Acontrol Switch Module for Hydraulic Couplers

Background

Our background and experience is in the supply of hydraulic attachments for excavators and other earthmoving machinery. Traditionally excavator buckets have been attached to the arm of the machine by two manually inserted pins. Over the last twenty years the use of devices to assist connection, making the process quicker and safer, has increased dramatically. These devices are known in the industry as couplers and are mounted to the end of the machire arm, either permanently or semi-permanently and may be mechanically or hydraulically operated to connect the bucket or other tool to the machine. In recent years there has been much publicity surrounding the use of couplers following several fatalities where buckets have become detached from the machine. Whilst many manufacturers have strived to increase safety elements within the mechanics of the coupler itself, the simple operation and potential ambiguity for the operator of switch operation or control sequence have not been improved or considered to the same degree.

There are many different types and designs of coupler known in the prior art. This invention relates to the hydraulically operated type only.

All hydraulic couplers use an electrically operated valve mounted in a hydraulic circuit to control the activation and operation of the coupler. A typical example of a hydraulic coupler circuit is shown in drawing 3.

Hydraulic couplers have varying levels of complexity and use different operating sequences, in the effort to improve safety and / or gain competitive advantage. However, all rely on a simple switch for their operation, as they all use electrically controlled hydraulic valves, but there is no standard operational switch. Some may be operated by use of a simple toggle switch, some have locking switches (to minimise the risk of accidental operation). Others may have two buttons or switches, one of which may be of the hold-to-run type. All now tend to have a warning buzzer that operates simultaneously.

Statement of Invention:

This invention is concerned with the switch arrangement that controls the coupler valve only. It is designed to improve the safe operation of hydraulic couplers fitted to earthmoving machinery and other vehicles, by minimising the risk of incorrect or accidental activation.

The problem it addresses is that a machine operator may be laced with driving different machines with different types of coupler, operational sequence and switching, possibly on the same day. The equipment may be owned by the company he/she works for, or hired in plant may used. The operator may be generally unfamiliar with the vehicle, albeit trained to operate the type. It is possible that the same type of coupler has been installed on different machines but different control switches have been used.

The operation of this invention is sequential and incorporates an automatic return to the last switch position following electrical power interruption. This is an extremely important safety feature. For example, should the operator have to switch off the engine during the coupling procedure, for any reason, when the machine is re-started the module will return to the last position that it was in prior to the power interruption. Furthermore it is not possible to operate the module out of the sequence described.

The invention is equally relevant to a hydraulic coupler mounted on a front-end loader, crane arm, or othervehicle.

Drawings.

There are four accompanying drawings: 1: The preferred form of the coupler switch module.

2: A flow chart showing the switching sequence and effect.

3: A schematic of a typical hydraulic coupler control circuit.

4: Illustration of the preferred control box form.

Detailed Description

This invention is a control switch module which can be used to operate the control valve of all types of hydraulic coupler to improve safety. The main benefit to a business running a fleet of machines is that they can all have a common control switch regardless of the type of coupler fitted to the machine, thus avoiding potential confusion. It incorporates some features that in isolation are not novel, but are when brought together as a whole in the present invention, for this operation. It can be retro-fitted to any vehicle for very low cost.

A preferred form of the present invention is now described with reference to the accompanying drawings: With reference to drawing 1, the control switch module comprises two switch buttons in a sealed membrane keypad (3) mounted in a composite plastic, or similar, box, in which is contained a pre-programmed printed circuit board. The first button (1.) is the power on switch, button (2) is the coupler lock activation button. Both buttons are labelled with industry standard symbols. Between the buttons is a LED light (4), which displays status accordingly. The module further contains an audible warning system (6) that produces intermittent and continuous tones. Preferably the module has two predefined lengths of cable attached, (5) one to connect to the power source, one to connect direct to the coupler control valve. This negates the need for interference with any of the vehicle's existing wiring and simplifies installation. The casing is held together by tamper-proof screws (7) to deter interference. It is water resistant so as to be unaffected by normal washing of the vehicle.

The module box is preferably rectangular to the proportions illustrated in drawing 4-of lightweight and smooth-sided construction to facilitate installation or positioning in the operator's cabin in virtually any suitable position. Positioning is preferably by use of adhesive material pads, to avoid drilling of the cabin structure. However, the module box may be mounted by any other means.

The operating sequence is now described and is supported by the flow chart on drawing 2, and drawing 3, the coupler control circuit schematic.

When the vehicle ignition is turned on power is supplied to the module which runs a self-diagnostic test to confirm functionality -a green light is continuously displayed via the LED if all is o.k. If this is not the case, with a fault being detected in the circuit, a solid red light is shown and the module is inoperable.

When the coupler is required to operate, button 1 (power) is pressed for one second. The indicator LED 14) will turn from continuous green to flashing red and an intermittent warning tone will be heard. This indicates that power is now connected to the coupler electrical circuit in readiness for operation of the hydraulic valve. Button 2 (the lock control) is now pressed for one second. The LED indicator will display continuous red and a continuous warning tone will be heard. This indicates that electrical power is now connected to the coupler valve (drawing 3, item 10) and that the coupler hydraulic circuit is unlocked and operable. The bucket or other tool can now be changed as required via the action of the coupler cylinder (drawing 3, item 12). Once the implement change is complete button 2 is pressed for one second. The LED will display flashing red and the intermittent warning tone will be heard indicating that the electrical power is now disconnected from the coupler valve and that the coupler hydraulic circuit is locked and inoperable. Button 1 is then pressed for one second, the intermittent warning tone will stop and the LED lamp will show continuous green indicating that the power is disconnected from the coupler electrical circuit and it is safe to operate the vehicle.

Claims

Claims 1. Ar electrical control switch module for the operation of the hydraulic valve of hydraulic couplers fitted to vehicles, whereby the two-button, failsafe sequential operation of the module reduces the risk of accidental activation of the coupler hydraulic circuit; and said module incorporates a pre-programmed printed circuit board with self-diagnostic fault detection, whereby the coupler is rendered inoperable on fault detection, and where the module returns to the last sequential position following an interruption to the power supply.
2. Preferably said module as per claim one is contained within a water resistant and tamper-proof box with power input and output cables pre-installed, said box preferably made of smooth-sided material.
3. Said operational buttons as per claim one are preferably of the sealed membrane push type.
4. Module as per claim one preferably incorporates a two-tone audible warning system, and warning light, preferably low energy display, capable of displaying two colours, preferably, but not limited to, green and red, and intermittent red.
5. A switch module as described in the preceding claims and with reference to any one of the accompanying drawings.