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EP-4741240-A1 - PNEUMATIC SYSTEM

EP4741240A1EP 4741240 A1EP4741240 A1EP 4741240A1EP-4741240-A1

Abstract

A pneumatic system comprises a first compressor and associated first air dryer for supplying dried air to a first set of consumers in a main circuit and a second compressor and associated second air dryer for supplying dried air to at least one further consumer through a subsidiary circuit. A protection valve system is provided in the main circuit between the first air dryer and the first set of consumers. A fluid flow path is provided between the main and subsidiary circuits which is selectively openable or closable by a coupling valve to enable the subsidiary circuit to be supplied with pressurized air from the main circuit or to isolate the main and subsidiary circuits.

Inventors

  • KLAUS, MICHAEL
  • Albrecht, Tobias
  • Bosl, Markus

Assignees

  • AGCO International GmbH

Dates

Publication Date
20260513
Application Date
20251105

Claims (17)

  1. A pneumatic system, comprising: a first compressor (200); a first air dryer (210) having an input (211) coupled to an output (200a) of the first compressor and an output (212) coupled to a first set of consumers (222a, 222b) in a main circuit (220), the main circuit (220) having a multi-circuit protection valve system (280) downstream of the first air dryer (210) which outputs to a number of sub-circuits to supply the consumers (222a, 222b) of the first set (220) of consumers; a second compressor (250); a second air dryer (260) having an input (261) coupled to an output (250a) of the second compressor and an output (262) coupled to at least one further consumer in a subsidiary circuit (270); and a fluid flow path (300) between the main circuit (220) and the subsidiary circuit (270), the fluid flow path (300) including a coupling valve (302) which is controllable to selectively open and close the fluid flow path.
  2. The pneumatic system of claim 1, wherein the fluid flow path (30) is connected to the main circuit downstream of the multi-circuit protection valve system (280).
  3. The pneumatic system of claim 1 or claim 2, further comprising a one-way fluid coupling (290) between the main circuit (220) upstream of the protection valve system (208) and the output of the second air dryer (260), enabling flow from the second air dryer to the main circuit 220 such that, in use, the first and second compressors can together supply the first set of consumers (220).
  4. The pneumatic system of any one of claims 1 to 3, wherein the coupling valve (302) is an electrically controlled valve.
  5. The pneumatic system of any one of claims 1 to 4, wherein the fluid flow path comprises a pressure relief valve (304) in series with the coupling valve (302).
  6. The pneumatic system of any one of claims 1 to 5, wherein the first compressor (200) is a single cylinder compressor.
  7. The pneumatic system of any one of claims 1 to 6, wherein the first air dryer is an electrically operated air dryer.
  8. The pneumatic system of claim 7, wherein the first air dryer (210) comprises an electrically operated single chamber air dryer having an input coupled to the first compressor and an output coupled to the first set of consumers through the main circuit, the air dryer comprising a dryer unit and a regeneration system.
  9. The pneumatic system of any one of claims 1 to 8, wherein the second compressor (250) is a double cylinder compressor.
  10. The pneumatic system of any one of claims 1 to 9, wherein the second air dryer (260) is a double chamber air dryer or an electrically operated air dryer.
  11. The pneumatic system of any one of claims 1 to 10, wherein the first and second compressors are driven by the same power source (310), and wherein the system comprises a clutch (312) between the power source and the second compressor.
  12. The pneumatic system of any one of claims 1 to 11, wherein the at least one further consumer requires a higher air flow rate in at least some operating conditions than the consumers of the first set.
  13. The pneumatic supply system of any one of claims 1 to 12, where the at least one further consumer comprises an air supply circuit of a tire pressure control system.
  14. A vehicle comprising: the pneumatic system of any one of claims 1 to 13; and the consumers (222a, 222b, 272) that are supplied by the pneumatic system.
  15. The vehicle of claim 14, wherein the first set of consumers comprises one or more selected from the following list: rear service brake; front service brake; park brake; trailer brake.
  16. The vehicle of claim 14 or 15, wherein the at least one further consumer comprises one or more selected from the following list: tire pressure control system (320); cab air supply; dust discharge system.
  17. The vehicle of claim 16, wherein the at least one further consumer comprises a tire pressure control system (320) having a supply circuit through which air is provided to at least one tire of the vehicle and a control circuit having a valve manifold for controlling the supply circuit, and wherein a valve manifold supply pressure (330) is provided from the main circuit, through a pressure regulating valve (332).

Description

FIELD Embodiments of the present disclosure relate generally to pneumatic systems, in particular pneumatic supply systems, especially for industrial or utility vehicles, such as tractors, other agricultural vehicles, construction vehicles and others. BACKGROUND Pneumatic air supply systems for vehicles typically comprise a compressor that provides a compressed air supply to a range of different pneumatic consumers (i.e., system hardware such as pneumatic actuators, pneumatic cylinders and pneumatic motors together with associated actuating valves and reservoirs/accumulators for storing a pressurized air supply for such equipment) on the vehicle and/or on an associated implement attached to or towed by the vehicle. Some consumers may be regarded as primary consumers whose operation is prioritized over other consumers that are regarded as secondary. Primary consumers may be safety critical, such as pneumatic brake systems, for example. Examples of secondary consumers include a pneumatic cab suspension system, pneumatic driver seat suspension system, pneumatic engine brake system and a tire pressure control system (TPCS). It is known for a TPCS to have two circuits: a supply circuit which supplies air to the tires when being inflated, and a control circuit which is used to actuate valves to control the supply circuit. A TPCS may be used to deflate the tires (e.g. on a tractor) when a vehicle is used in a field as this improves grip and reduces soil compaction and to reinflate the tires to a higher pressure when the vehicle is driven on the road. With this arrangement, it is necessary to reinflate the tires when transitioning from field use to road use. This needs to be done as quickly as possible, hence there is a need for a high flow rate but low-pressure air supply in the TPCS supply circuit whereas the control circuit requires a higher pressure but low flow rate supply. Air from the compressor is usually passed through an air dryer to discharge humidity from the air before supplying it to the consumers system a vehicle. A multi-circuit protection valve system is often provided between the air dryer and the consumers. The multi-circuit protection valve system is operative to balance the pressure required to be supplied to the primary of consumers and the secondary consumers and/or to cut the supply to any consumer should the consumer or its supply circuit develop a leak. In this way, the integrity of the supply to the remaining consumers is maintained. Furthermore, the multi-circuit protection valve system may be configured to ensure that the supply to the primary consumers is prioritized over the supply to secondary consumers. Different consumers on a vehicle will often have different requirements in terms of flow rate and air pressure. Most consumers, including safety-critical pneumatic brake circuits, require a relatively low flow rate but high-pressure air supply. However, some consumers require a relatively high flow rate but a lower pressure. This is the case for example with the supply circuit of a TPCS through which air is introduced into the tires. In certain circumstances, meeting the demand of a high flow rate secondary consumer can potentially impact on the ability of the pneumatic system to meet the demands of the primary consumers. BRIEF SUMMARY The scope of this disclosure is defined by the claims. According to examples in accordance with this disclosure, there is provided a pneumatic system according to claim 1. Further optional features are set out in the claims dependent on claim 1. A vehicle comprising the pneumatic system is also provided. BRIEF DESCRIPTION OF THE DRAWINGS One or more embodiments of this disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which: FIG. 1 shows a tractor, as one example of a vehicle that can make use of the pneumatic system of this disclosure; andFIG. 2 shows a pneumatic circuit of this disclosure. DETAILED DESCRIPTION The subject matter of this disclosure will be described with reference to the Figures. It should be understood that the detailed description and specific examples, while indicating exemplary embodiments of the apparatus, systems and methods, are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. These and other features, aspects, and advantages of the apparatus, systems and methods of the present disclosure will become better understood from the following description, appended claims, and accompanying drawings. It should be understood that the Figures are merely schematic and are not drawn to scale. It should also be understood that the same reference numerals are used throughout the Figures to indicate the same or similar parts. This disclosure provides a pneumatic system comprising a first compressor and associated first air dryer for supplying dried air to a first set of consumers in a main circuit, and a second compressor and associated