AU663815B2

AU663815B2 - Plate valve particularly for compressors

Info

Publication number: AU663815B2
Application number: AU53173/94A
Authority: AU
Inventors: Gerald Pavlu
Original assignee: Hoerbiger Ventilwerke GmbH and Co KG
Current assignee: Hoerbiger Ventilwerke GmbH and Co KG
Priority date: 1993-02-15
Filing date: 1994-01-13
Publication date: 1995-10-19
Anticipated expiration: 2014-01-13
Also published as: TW262521B; DE59400034D1; CN1096856A; AT401550B; AU5317394A; KR940019996A; EP0611889A1; ATA27093A; EP0611889B1

Description

-1-6381,5

AUSTRALIA

Patents Act 1990 HOERBIGER VENTILWERKE AKTIENGESELLSCHAFT

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT C (C C C~CC C I C 9 C IC C I C

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IC I f I Invention Title: Cs..

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Cc Cl C C "Plate valve particularly. for compressors" The following statement is a full description of this invention including the best method of performing it known to us:- Plate valve, particularly for compressors The invention concerns a plate valve, particularly for compressors, with a valve seat, a guard provided at a distance from the latter and plates provided between the valve seat and the guard, in fact a closing plate which controls the flowthrough channels of the valve seat, as well as at least one auxiliary plate assigned to the closing plate, e.g. a spring, attenuating or guiding plate which is fixed relative to the 10 guard.

Plate valves of this type are known with different constructions. During the operation of such a valve the closing 4. 4 .plate carries out a reciprocating movement between the valve seat and the guard, closing and opening alternatively the flowthrough channels of the valve seat. The task of the auxiliary plates is to exert a flexible load on the closing plate ae 2 relative to the valve seat, so that the valve would be closed in the unpressurised state also, to attenuate the impacts of the closing plate on the guard and to absorb them, if necessary, during the reciprocating movement.

To carry out correctly these tasks and to avoid as far as possible the sliding frictions on the guiding surfaces, in the Cttttg known constructions the auxiliary plates are, as a rule, fixed in the valve, in most cases by means of their central boss I clamped between the guard and a distance ring provided between the guard and the valve seat. Other constructions are also known, wherein the auxiliary plates are simply screwed on the guard radially outside of the boss.

In the known constructions the fixing of the auxiliary plates in the valve is relatively complicated. The use of a distance ring means a component of its own, which not only makes the production of the valve more expensive, but also complicates the assembly. The space requirement of a distance or guide ring in the centre of the valve is also relatively big, due to which the potential flow-through cross-section of the valve is 2 S. a S eq *5 Wa sr S a

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C C reduced. In case of auxiliary plates directly screwed onto the guard's surface the expense is even greater, as more screws must be provided and fitted, which, in addition, may be in the way when attaching the closing plate on the guard.

It would be desirable to improve and simplify the known plate valves of the type of construction mentioned above, so that the auxiliary plates provided can be simply and rapidly fastened in the valve by using only a few components.

The present invention provides plate valve, particularly for compressors, having: a valve seat; a guard provided at a distance from the valve seat; and two or more plates provided between the valve seat and the guard including a closing plate which controls flow-through channels of the valve seat, and at least one auxiliary plate assigned to the closing plate which is 20 fixed relative to the guard; wherein the guard has a guard boss which projects against the valve seat, and which is provided with at least one radial recess; wherein the auxiliary plate has a cut-out in its centre which is larger than the cross-section of the guard boss and has at least two brackets which project past the auxiliary plate's inner edge; and wherein the brackets can be snapped into a recess of the guard boss by placing the auxiliary plate with its central cut-out onto the guard boss and by a relative movement between the guard and the auxiliary plate.

Thus the guard in the valve construction is provided with a boss, which may be integral with it, so that not a single distance or guide ring between the valve seat and guard is necessary. During assembly the auxiliary plate constructed accordingly needs only to be placed onto this o 2/1 guard boss and anchored by a relative movement to achieve a secure fixing in the valve and to enable a friction-free movement of this plate. Just one or several recesses are required in the guar,' boss, their width corresponding to the number of the to-be-accommodated auxiliary plates, which recesses can be easily produced. Thus the construction according to the invention is characterised by its simplicity, its easy assembly without tools and only few components.

In a preferred embodiment of the invention the guard boss is constructed with a non-circular cross-section and in the axial direction it has flattenings of the circular shape or recesses a* p t St I L

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which fit the brackets of the associated auxiliary plates, while the auxiliary plate can be placed in the axial direction onto the guard boss and through rotation can be snapped into 4Ahis cornssfrucon. the recesses of the guard boss. I cac of thic conu.tion -teethe guard boss can be easily produced as only relatively small flattenings or recesses are necessary, which can be easily produced by milling or grinding.

A further advantageous embodiment of the invention is that the guard boss has two diametrically opposed recesses and the recess provided in the centre of the auxiliary plate fits the guard boss eccentrically, while after placing the auxiliary plate onto the guard boss the brackets can be snapped into the recesses of the guard boss by moving the auxiliary plate in its plane. In this case the guard boss can retain its cylindrical cross-section; it must be provided only with recesses to accept the brackets. In any case the recess in the centre of the auxiliary plate must be somewhat larger, so that this 0 construction requires a somewhat larger space.

0 In a further development of the invention the brackets of the auxiliary plate can be domed at least in the region engaging ^the recesses of the guard boss, aenerated preferably with a 2 line which is parallel to a radius of the guard boss and flexibly pretensioned snap into the recesses of the guard boss.

At the same time the brackets are elastically deformed when pushed into the recesses of the guard boss, so that they fill the recesses flexibly and are anchored in these without any play. The frictional forces arising on this occasion prevent an unintentional release of the brackets from the recesses and consequently also a disadvantageous loosening of the auxiliary plate fixed in the valve.

ji Within the framework of the invention a further improvement of the fixing can be achieved by that at least one axial bore is provided in the guard boss, which bore intersects at least one f of the recesses serving to accommodate one bracket of the auxiliary plate and into which a pin can be inserted, which 3 after the snapping in of the bracket in the respective recess engages the bracket. Consequently the brackets are secured in the respective recess of the guard boss by a simple pin, so that the auxiliary plate can neither snap out nor rotate from its fixed position.

tat h auxipiarfry lt a nihrsapotnrroaefo An approprite construction is that the pins inserted in the axial bores have grooves in the region of the recesses of the guard boss which grooves and recesses are aligned with each 10 other, into which grooves the brackets can be pushed in, while in the brackets roughly semi-circular recesses are provided with which, when rotated, the pins engage with their side averted from the groove. In this conjunction the pins do not need to be pushed into the guard boss only after the brackets have been inserted into the recesses of the guard boss. The grooves in the pins make the insertion of the brackets feasible even with the pins inserted. Thus the final anchoring is oQ carried out just by rotating the pins.

According to the invention the pins may sit in blind holes, which originate from the side of the valve seat, are covered by these against falling out and for the purpose of rotation are provided on their end face with an application profile for a I tool, e.g. a transversal slot for a screwdriver.

es o preef~n Finally, one version of the fixing according to the invention is that the pins protrude from the blind holes in the guard towards the valve seat and engage the blind holes provided in the valve seat. Consequently, these pins also serve the purpose of positioning the valve seat relative to the guard plate, due to which additional devices like pins or markings may be omitted. At the same time the pins projecting from the guard boss can be simply grasped and rotated. Although this facilitates the assembly, additional, even if short, blind holes are necessary in the valve seat.

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Further details and advantages of the invention become apparent from the following description of the embodiments, which are illustrated in the drawings.

They show the following: Fig.l a central cross-section through an embodiment of the valve according to the invention, 1 C 10 Fig.2 a central cross-section through the guard, Fig.3 a top view on the guard, Fig.4 an axial cross-section of a detail on a larger scale, a section along line V-V of Fig.4, Fig.6 an axial cross-section of a detail of a further embodiment on a larger scale, S" Fig.7 a section along line VII-VII of Fig.6, Fig.8 a cross-section across a bracket of an auxiliary plate.

t C According to Fig.l the valve according to the invention, illustrated as an example, consists of a valve seat 1 and a guard plate 2, which is held together with the valve seat 1 by means of a central bolt 3. Between the valve seat 1 and the guard 2 a closing plate 4, which may be made of plastics, and one or more auxiliary plates 5, e.g. spring, attenuating or guiding plates are situated. In the valve seat 1 flow-through channels 6 are provided, which are controlled by the closing plate 4, and in the guard 2 flow channels 7 are provided. In the centre of the valve a pin 8 and a guard boss 9 can be seen.

It can be seen from Fig.2 that the guard 2 has an integral guard boss 9, which is provided with an axial bore 10, into I which the pin designated by 8 in Fig.l, can be inserted. In p "y ii II Fig.3 two pins 8 can be recognised in the guard boss 9, which are situated diametrically opposite each other. On the outer edge of the guard boss 9 an annular recess 11 is provided shaped as a radially outwards open groove and shown in a dotted line and between the two pins 8 at an angle of approx. flattenings 12 are formed on the guard boss 9 by milling or grinding.

Figs.4 and 5 show more exactly the construction of the 10 illustrated valve in the region of the guard boss 9. In Fig.4 the central part of the valve seat 1 and of the guard 2, the closing plate 4 and the two auxiliary plates 5 are shown.

Furthermore, the guard boss 9 and two pins 8 can be recognised.

Both auxiliary plates 5 protrude with their inner edge into the recess 11, which is provided in the guard boss 9.

It can be further seen in Fig.5, that the guard boss 9 has a non-circular cross-section in this case also. The two S flattenings 12 are situated diametrically opposite each other.

The auxiliary plate 5 illustrated here is placed on the guard boss 9 so, that with the projecting brackets 13 it lies against the flattenings 12. By rotating the auxiliary plate 5, slightly in the direction of the arrow 14, but also in the opposite I direction, the short arms 13 engage the recesses 11 of the boss i 9, and after being rotated by approx. 90° reach the region of the pins 8. Roughly in the centre of the brackets 13 a semicircular recess 15 each is provided, with which the pins 8 engage.

During the rotation of the auxiliary plate 5 the pins 8 are slightly lifted. As soon as they are aligned with the semi- i circular recesses 15, they are inserted into these. According j to Fig.4 the top ends of the pins 8 engage the blind-holes 16 of the valve seat 1, their falling out thus prevented. These pins 8 thus prevent an unintentional rotation of the auxiliary j plate 5, so that these will be held firmly in their predetermined positions.

a The embodiment according to Figs.6 and 7 differs from the above described embodiment mainly by that the auxiliary plate 5 is placed eccentrically on the guard boss 9, while this can have a circular cross-section. It can be seen from Fig.7, that the guard boss 9 has two diametrically opposed recesses 11, each of which is penetrated by a pin 8. According to Fig.6 the pins 8 themselves have grooves 17, which are aligned with the recesses 11 when the pins 8 are inserted.

It can be further seen from Fig.7, that the auxiliary plate t with its cut-out fits eccentrically the guard bo.s 9. It is, t itherefore, pushed onto the guard boss 9 in the position illustrated in Fig.7, whereupon the auxiliary plate 5 is nioved in its plane in direction of arrow 14, resulting in both brackets 13 engaging the recesses 11 of the guard boss 9 and penetrating the grooves 17 of the pins 8. As soon as the brackets 13 with their semi-circular recesses 15 reach the tr" region of the pins 8, the pins can be rotated by approx. 180°, c due to which the full half of the pins 8 passes through the region of the semi-circular recesses 15. The auxiliary plates will be fixed by this relative to the guard boss 9.

To rotate the pins 8 they are provided on their end faces with t« r( r an application section for a tool, in the case of the 25 embodiment with a transversal slot 18, like it is shown, for example, in Fig.6, the purpose of which is to accept a screwdriver. The pins 8, which sit in a blind hole of the guard a boss 9, are covered by the valve seat 1 and thus are secured against falling out.

Fig.8 shows a view of a version of the bracket 13. As this can be seen from the illustration, the brackets 13 can be I constructed slightly domed, so that they are pushed together flexibly when they are pushed into the recesses 11 of the guard boss 9. In this manner the auxiliary plates 5 are held firmly without any play. In case of adequate spring force the pins 8 as a safety feature may be omitted.

7 -1 II I The auxiliary plates 5 may be, as has already been explained, spring, attenuating or guiding plates. Most frequently the spring plate is being used, because practically all modern plate valves have springs. For this purpose both the classic spring plat.es with arms curving out of their plane can be used, as well as the so called wavy ring springs, which are made of closed rings, whose annular section is curved from the plane of the plate in both directions of the spring plate. Otherwise formed spring plates are also conceivable, e.g. so called sinus; c L4 10 springs with cylindrical dome or disk springs. It is also feasible according to the invention to fix different types of plates in the same valve, e.g. spring and attenuating plates, S if necessary, at different distances from the guard.

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Claims

1. Plate valve, particularly for compressors, having: a valve seat; a guard provided at a distance from the valve seat; and two or more plates provided between the valve seat and the guard including a closing plate which controls flow-through channels of the valve ieat, and at least one auxiliary plate assigned to the closing plate which is fixed reJative to the guard; wherein the guard has a guard boss which projects against the valve seat, and which is provided with at least one radial recess; t' cwherein the auxiliary plate has a cut-out in its 15 centre which is larger than the cross-section of the guard boss and has at least two brackets which project past the auxiliary plate's inner edge; and f wherein the brackets can be snapped int- a recess of the guard boss by placing the auxiliary plate with its central cut-out onto the guard boss and by a relative movement between the guard and the auxiliary plate.

2. Plate valve according to claim 1 where.t, the relative movement between the guard and the biK-iliary i plate is by rotating or moving the auxiliary plate in its 1 c 25 plane. !I e c:

3. Plate valve according to claim 1, characterised in that the guard boss is constructed with a non-circular cross-section in that it has flattenings or recesses in an t otherwise generally circular shape which extend in its axial direction and which fit the brackets of the associated auxiliary plates, while the auxiliary plate can be placed in the axial direction onto the guard boss and through rotation can be snapped into the recesses of the guard boss.

4. Plate valve according to claim 1, characterised in that the guard boss has two diametrically opposed recesses I i r 62507/TJB/awc/h9 FRE SCHILLING Reiastered Patent Attorney 9 0 9* ttt r tr and the recess provided in the centre of the auxiliary plate fits the guard boss eccentrically, while after placing the auxiliary plate onto the guard boss the brackets can be snapped into the recesses of the guard boss by moving the auxiliary plate in its plane.

Plate valve according to any one of claims 1 to 4, characterised in that the brackets of the auxiliary plate are domed at least in the region engaging the recesses of the guard boss, generated preferably with a line which is parallel to a radius of the guard boss and flexibly pretensioned snap into the recesses of the guard boss.

6. Plate valve according to any one of the claims 1 to characterised in that at least one axial bore is provided in the guard boss, which bore intersects at least 15 one of the recesses serving to accommodate one bracket of the auxiliary plate and into which a pin can be inserted, which after the snapping in of the bracket in the respective recess engages the bracket.

7. Plate valve according to claim 6, characterised in that the pins inserted in the axial bores have grooves in the region of the recesses of the guard boss which grooves and recesses are aligned with each other, into which grooves the brackets can be pushed in, while in the brackets roughly semi-circular recesses are provided with which, when rotated, the pins engage with their side averted from the groove.

8. Plate valve according to claim 6 or 7, characterised in that the pins sit in and are retained by blind holes which originate from the side of the valve seat, and for the purpose of rotation are provided on their end face with an application profile for a tool, e.g. a transversal slot for a screwdriver.

9. Plate valve according to claim 6 or 7, characterised in that the pins protrude from the blind holes in the guard towards the valve seat and engage the blind holes provided in the valve seat. 1 Plate valve as hereinbefore described with reference to the accompanying Figures 1-5 or 6-8. DATED this 11th day of August 1995 HOERBIGER VENTILWERKE AKTIENGESELLSCHAFT Patent Attorneys for the Applicant: F.B. RICE CO. *t C Abstract A plate valve, which is suitable particularly for compressors, consists of a valve seat a guard provided at a distance from the latter and plates provided between them, in fact a closing plate and at least one auxiliary plate To simplify the fixing of the auxiliary plates in the valve, the guard with a guard boss projects against the valve seat and in the guard boss at least one recess (11) is provided. The auxiliary plates are provided with brackets (13) and have a cut-out in their centre. They are placed onto the guard boss following which the brackets (13) can be snapped into the recesses (11) of the guard boss by a relative movement between the guard and the :15 auxiliary plane o e rr i t r ,r r j i~Lf V