GB2214615A

GB2214615A - A valve set for a reciprocating compressor

Info

Publication number: GB2214615A
Application number: GB8901169A
Authority: GB
Inventors: Hans Meier; Marcel Pawlicek
Original assignee: Maschinenfabrik Burckhardt AG; Maschinenfabrik Sulzer Burckhardt AG
Current assignee: Burckhardt Compression AG
Priority date: 1988-01-19
Filing date: 1989-01-19
Publication date: 1989-09-06
Anticipated expiration: 2009-01-19
Also published as: FR2626045A1; GB2214615B; IT1228285B; BE1001997A3; GB8901169D0; FR2626045B1; AT403190B; BR8900189A; IT8919017A0; ATA589A; CH674757A5

Description

1 1; 1 A Valve Set for a RecilDrocatinq ComDressor r, 2 14 6 'i 5 A- The

invention relates to a valve set for a reciprocating compressor, the set comprising an inlet valve and, disposed concentrically thereof, a delivery valve, each of the valves having a perforate seat plate, valve plates which are associated one each with the inlet valve and delivery valve being disposed between the two seat plates and each being held between the seat plates by at least one link.

A valve set of this kind is known f rom. Fig. 2 of DE-AS 18 12 580. In this known valve set the two seat plates are clamped together by a central screw and nut connection and the link arms which are connected to the outside of the two valve plates are held at their free ends by pins which are disposed in the seat plates. Between, on the one hand, the pins which retain the link arms of the inner valve plate and, on the other hand, the inner edge of the outer valve plate there is a relatively substantial radial distance and sealing means between the two seat plates are necessary in this zone to ensure gas-tight separation of the inlet valve from the delivery valve. In this valve set construction the valve set must be of relatively large diameter and therefore takes up a correspondingly large space in the compressor.

It is an object of the invention so to improve a valve set of the kind set out that its diameter and, therefore, the space it requires are reduced.

According to the invention, therefore, the inner edge of the outer valve plate and the outer edge of the inner valve plate each have a closed ring connected to the associated link and the two valve plates are 2 sealingly secuped between the seat plates at these two closed rings. By the provision of adjacent closed rings which can be given relatively narrow dimensions it is possible to concentrate the securing of the two valve plates between the seat plates over a narrow annular zone so that the largest diameter of the valve set can be greatly reduced in comparison with that of the previous construction described. Nor is there any need for any central screw connection of the seat plates, and this can also reduce the diameter, since the space which can be freed at the axial centre of the valve set is now available for the gas f low. it is very easy to make the new valve set, the two valve plates first being made in one piece which is then finally separated into the two valve plates by means of a laser cutting process.

The invention may be carried into practice in various ways but one valve set embodying the invention will now be described by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a section through the valve set on the line I-I of Fig. 2, and Fig. 2 is a plan view of the two valve plates disposed one inside the other, to a somewhat reduced scale compared with Fig. 1.

Referring to Fig. 1 the valve set mainly comprises two seat plates 1,2, disposed one above the other, and two valve plates 3,4 disposed between the two seat plates 1 and 2. The seat plate 1 co-operates by way of its central part with the inner valve plate 3 to form an inlet valve f or a compressor which is not shown in further detail and whose compression chamber 5 extends below the seat plate 2. A delivery valve of annular 1 1 3 cross-section is f ormed by the outer ring part of the seat plate 2 and of the annular valve plate 4. The seat plate 1 is formed in its central part with slotlike perforations 6 which extend on arcs concentrically of central axis 7 of the valve seat but do not extend through a complete circle. The seat plate 2 is formed below the central part of the seat part 1 in Fig. 1 with slot-like perforations 8 which extend in the same way as the perforations 6 but are offset outwardly therefroin by half a radial pitch. The perforations 8 widen diffuser-fashion towards the compression chamber 5. Also, a perforation 81 which is widened diffuserfashion is disposed at the centre of the seat plate 2. Perforations 20 which register with the perforations 8,81 are disposed in the valve plate 3.

Eight springs 9 press the plate 3 of the inlet valve on to the seat plate 1. The distribution of the springs 9 over the valve plate 3 is shown by broken-line circles in Fig. 2. The springs 9 are disposed in corresponding pockets 90 in the seat plate 2. The gas for compression flows through the central part of the seat plate 1 in the direction of the arrow 10, the valve plate 3 being moved downwards against the force of the springs 9 so that the gas enters the compression chamber 5 via the perforations 6 and 20; 8 and 81.

The annular delivery valve of the valve set extends concentrically around the inlet valve. Four springs not visible in Fig. 1 press the valve plate 4 on to the seat plate 2. The latter springs therefore correspond to the springs 9 but are received in the top seat plate 1, being distributed over the zone of the valve plate 4 (broken-line circles in Fig. 2). The 4 seat plate 2 is also formed with slot-like perforations 12 which correspond to the perforations 6 in the seat plate 1 and which also extend on a circle arc but not over the entire periphery. Perforations 13 in the seat plate 1 are associated with the perforations 12. Perforations 21 which register with the inwardly disposed perforations 13 are disposed in the valve plate 4. During the compression phase, the compressed gas flows of f in the direction of the arrow 14, the valve plate 4 being lifted away from the seat plate 2. The entering gas for compression (arrow 10) and the departing compressed gas (arrow 14) are separated from one another by an annular closed wall indicated by chain-dotted lines 15 in Fig. 1.

Referring to Fig. 2, the valve plates 3 and 4 are disposed concentrically one inside the other. The outer valve plate 4 is connected via four link arms 4f to an inner closed securing ring 411. The inwardly situated valve plate 3 is similarly connected to an outer securing ring 311 via four outer link arms 31.

Referring to Fig. 1, the closely adjacent securing rings 311, 411 are clamped between the seat plates 1 and 2. The clamping force is provided by four screws 16, only one of which is visible in Fig. 1 and which are operative to clamp the seat plates 1, 2 together. A semi-circular notch 17, visible in Fig. 2, for the screws 16 is provided in the respective transition regions of the link arms 41 and the securing ring 411. The link arms 31 and 41 ensure that the valve plates 3 and 4 are mobile relatively to the respective securing ring 311, 4 11.

The valve plates 3 and 4 are initially made in one piece and are divided into the two plate parts by a 1 laser severing cut 22 at the end of the operation, the cut which is otherwise circular being given a small inwardly projecting semicircle 23 by means of which the securing ring 411 receives a nose which projects into a semicircular groove. This obviates relative turning of the two plates 3 and 4 during assembly.

As a variant of the embodiment described, the notches 17 of Fig. 2 can be shifted anticlockwise as far as the 450 line, in which event the transition zone between the link arms 4' and the valve plate 4 is also displaced or is of narrower dimensions than in Fig. 2. The advantage of this variant is that the valve plate 4 can also be turned over in the event of the surf ace which co-operates with the seat plate 2 becoming worn, so that the surface previously in engagement with the springs then co-operates with the seat plate 2.

6

Claims

Claims:

1. A valve set for a reciprocating compressor, the set comprising an inlet valve and, disposed concentrically thereof, a delivery valve, each of the valves having a perforate seat plate, valve plates which are associated one each with the inlet valve and delivery valve being disposed between the two seat plates and each being held between the seat plates by at least one link, the inner edge of the outer valve plate and the outer edge of the inner valve plate each have a closed ring connected to the associated link and the two valve plates being sealingly secured between the seat plates at these two closed rings.

2. A reciprocating compressor valve set substantially as described herein with reference to the accompanying drawings.

Published M9 atThe Patent Office, State House, 66,71 High Holborn, London WClR 4TP. Further copies maybe obtainedfromThePatentOfnce. Sales Branch, St Mary Cray, Orpington, Rent BR5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1/87 k 1