GB2262624A

GB2262624A - Input/output amplifier device entegrally mounted with hydraulic valve.

Info

Publication number: GB2262624A
Application number: GB9127146A
Authority: GB
Inventors: Christopher Charles Grayson
Original assignee: Vickers Systems Ltd
Current assignee: Aeroquip Vickers Ltd
Priority date: 1991-12-20
Filing date: 1991-12-20
Publication date: 1993-06-23
Also published as: GB9127146D0

Abstract

An input/output amplifier device 2 having first I/O lines 3-5, 8 accessible to a user and second I/O lines 9-12,15 not directly accessible to the user; the device further including detector means 25 connected between at least one of the first I/O lines and at least one of the second I/O lines and operable to detect the presence of at least one uncharacteristic signal applied to the or each first I/O line and in the presence of an uncharacteristic signal to activate the related second I/O line. The device is integrally mounted with a hydraulic valve 20. In response to an emergency, the user may place a high voltage or high current signal (as the uncharacteristic signal) on a spool position output line 8 which, through the detector means 25, triggers the disable line 9 to disable the valve. This reduces the number of first I/O lines needed. <IMAGE>

Description

INPUT/OUTPUT DEVICE The invention relates generally to an input/output device and has more particular, but not exclusive, reference to amplifier means suitable for use in hydraulic valve systems. Such arrangements are known as 'integral amplifiers', i.e. amplifiers integrally mounted with a hydraulic valve.

In the field of hydraulic valve systems, amplifiers have been traditionally disposed either remote from or integrally mounted to the valve. Industry standards have evolved governing the precise user interface characteristics of both configurations. Unfortunately, the standards adopted for the integral amplifier systems require that there be only 6 user interface input output (I/O) lines, related to a subset of basic amplifier functions. Systems based on the use of the remotely disposed amplifier systems (often a Eurocard implementation) are able to make use of many more normally available amplifier functions such as, for example, DISABLE, drive ENABLE and ramp ENABLE.

Accordingly, it is an object of the present invention to make available to the integrally mounted systems some of the functions which have hitherto only been available to systems having a remotely disposed amplifier, while still conforming to the accepted integral amplifier I/O standard.

The present invention provides an input/output device having first I/O lines accessible to the user and a plurality of second I/O lines not directly accessible to the user; the amplifier means further including detector means connected between at least one of the first I/O lines and at least one of the second I/O lines and operable to detect the presence of at least one uncharacteristic signal applied to the or each first I/O line and in the presence of an uncharacteristic signal to activate the related second I/O line.

The input/output device may be in the form of an amplifier means, which includes an amplifier.

The detector means may be responsive to a plurality of uncharacteristic signals to activate a single or a plurality of second I/O lines. The or each uncharacteristic signal may be characterised by its magnitude being outside the normal signal range, appearing on the or each first I/O lines with which the detector means is associated.

The amplifier means may be integrally mounted on a valve.

Exemplary embodiments of the invention are hereinafter described with reference to the accompanying drawings, in which: Figure 1 shows the logical layout of an amplifier means according to the present invention; Figure 2 shows an alternative arrangement to that shown in Figure 1; and Figure 3 shows a schematic view of an integral amplifier mounted on a hydraulic valve.

An integral amplifier means 1, as depicted schematically in Figure 3, includes an amplifier 2 which has a plurality of I/O lines which may be considered to comprise first I/O lines, which are user interface lines ie. lines which are directly accessible to the user, and second I/O lines which are not directly accessible to the user. A non-inverting demand input 3a, an inverting demand input 4, an input signal ground 5, power input lines 6, 7 and a spool position monitor output line 8 constitute the user interface first I/O lines. The user interface I/O lines are collectively denoted 30, as shown in Figure 3.

Valve control signal output lines 10, 11 and 12, the spool position monitor input line 15 and amplifier disable line 9 constitute the second I/O lines.

The disable line 9 is connected to the spool position monitor output line 8 via a detector means 25. The detector means 25 is operable to respond to a signal detected on the spool position output line a, which is outside the expected normal range, by triggering the disable line 9.

Thus, in using the system hereinbefore described, the user operates the valve in a manner comparable with a traditional integral amplifier valve system, that is the non-inverting and inverting demand input lines 3,4 have applied thereto signals indicative of the desired valve behaviour and the spool position monitor output line 8 provides a feedback and amplified measure of the current position of the spool within the valve 20, as is well known in the art. If the user then wishes to disable the valve 20 because, for example, an emergency has arisen, this is effected by the user applying a uncharacteristic signal, which in this embodiment is a large voltage Ve to the spool position monitor output line 8. This voltage V should be sufficiently large so as to be not encounterable under normal operating conditions.This voltage Ve is detected by the detector means 25 which, in response thereto, effects the disablement of the amplifier 2 by applying an appropriate signal to the disable input 9.

In an alternative embodiment of the invention (shown in Figure 2) the detector means 25 can be made responsive to the current output of the spool position monitor output line 8.

In other embodiments of the invention, further first I/O lines may be provided with further detector means 25 to permit thereby further functions of the amplifier means to be accessed. Although not described, these might include ramp enable, drive enable, for example.

In another embodiment of the invention, a given detector means 25 may be responsive to a plurality of uncharacteristic signals. For example, if a first output line in normal operation conveyed signals in the range of +Vrange the detector means may be responsive in a first predefined manner to a signal +Vrange + #V and responsive in a distinct second predefined manner to a signal -Vrange - #V, and thereby activate different functions of the amplifier according to the particular uncharacteristic signal detected.

The amplifier means l may be implemented as a plurality of discrete components mounted on a printed circuit board or alternatively as a single semiconductor package.

Claims

1. An input/output device having first I/O lines accessible to the user and a plurality of second I/O lines not directly accessible to the user; the amplifier means further including detector means connected between at least one of the first I/O lines and at least one of the second I/O lines and operable to detect the presence of at least one uncharacteristic signal applied to the or each first I/O line and in the presence of an uncharacteristic signal to activate the related second I/O line.

2. An input/output device as in claim 1, wherein the input/output device is in the form of an amplifier means, which includes an amplifier.

3. An amplifier means as in claim 2, wherein a plurality of detector means are provided.

4. An amplifier means as in claim 2 or 3, wherein the or each detector means is responsive to a plurality of uncharacteristic signals to activate a single or a plurality of second I/O lines.

5. An amplifier means as in any of claims 2 to 4, wherein a uncharacteristic signal applied to a first I/O line is characterised by its magnitude being outside the normal signal range, appearing on the or each first I/O line with which the detector means is associated.

6. An input/output device constructed, arranged and adapted to operate substantially as herein before described with reference to the accompanying drawings.

7. A valve arrangement including an amplifier means as in claims 2 to 6 wherein the amplifier means is integrally mounted on the valve.

8. A valve arrangement as in claim 7, wherein a first output line is provided with a detector#means.

9. A valve arrangement as in claim 7 or 8, wherein a first input line is provided with a detector means.

10. A valve arrangement as in claim 8, wherein a said first output line is the spool position monitor output line.

11. A valve arrangement constructed, arranged and adapted to operate substantially as herein before described with reference to the accompanying drawings.