GB1560365A

GB1560365A - Blade valve for compressors

Info

Publication number: GB1560365A
Application number: GB3428/78A
Authority: GB
Original assignee: Hoerbiger and Co
Current assignee: Hoerbiger and Co
Priority date: 1977-01-27
Filing date: 1978-01-27
Publication date: 1980-02-06
Also published as: ATA50177A; IT7819573A0; FR2379000A1; IT1092459B; PL204255A1; FR2379000B1; PL118547B1; DE2802378C2; DE2802378A1; AT353391B

Description

(54) BLADE VALVE FOR COMPRESSORS (71) We, HOERBIGER & Cho., of Im Forchet 5, D-8920 Schongau/Lech, Germany, a German Kommanditgesellschaft, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a blade valve for compressors, with a valve seat, of which the through opening is covered by at least one flexible blade, which at one end is clamped on the valve seat by a part which lies upon it and at the same time is secured there in its position at the through opening.

In blade valves, of which the closure members mainly consist of tongue-shaped blades, location of the blades is necessary, to ensure that these entirely cover the through opening in the valve seat. In this connection it is known to provide two parallel pins at the clamped end of the blade, which pins are anchored in bores of the valve seat, penetrate the blade and also engage in bores of the catcher. The pins must be very exactly arranged in the valve seat and the holes in the blades and in the catcher which they penetrate must be just as exactly formed, as any deviation from the constructional tolerances is additive because the pins lie relatively distant from the through opening of the valve seat This known construction is therefore relatively costly and requires very careful location and mounting.

It is also already known to secure the blade at its movable end. To this end the catcher is provided with a channel-shaped recess or with rib-shaped projections. so that lateral guide surfaces are formed at the free end of the blade. Another known device uses tangs cut out of the catcher, which tangs are either provided laterally at the free end of the blade or engage in a hole thereof. These methods of location assume that the catcher is suitablv positioned at the free end of the blade. Tn many cases, however, blade valves are con- structed without catchers, with merely aii abutment lying at some separation from the valve seat, or with a catcher which is bent outwardly and upwards away from the valve seat from the fixing position.In this way, the blade can perform a correspondingly large stroke with its free end. In the case of such valves, location at the free end of the blade is not practically possible.

According to the invention, there is provided a blade valve for a compressor, the valve comprising a valve seat having a through opening to be closed by a flexible blade valve member which is clamped at one end to the seat by a clamping member which lies over the blade and is rotationally fast with the blade, the seat having at least one depression in the area where the blade is clamped, and the blade being held in place by at least one projection on the clamping member which projects into said at least one depression.

The securing pins and the associated bores in the valve seat and in the catcher are thereby dispensed with. The costs of producing and mounting the valve are thereby considerably reduced. Furthermore, with the arrangement according to the invention, it is easier to adhere to the necessary tolerances than with the usual centering pins, as the projections and also the associated depressions in the valve seat can be simply formed by punching or stamping.

Tn a preferred form of the invention, further projections, consisting of tangs, are bent out of the blade and project into the depressions of the valve seat. The width of these tangs preferably tapers towards their free end. The tangs engage directly in the correspondingly contoured depressions of the valve seat, with the clamping member being located above the blade, with its projections also engaging in the depressions. The tapered construction of the tangs, the directions of whose side edgesneeds only to deviate by a few degrees from being parallel to each other, is advantageous for the arrangement of several blades one upon another, as the tangs can in each case engage without difficulty the recesses formed in the underlying blade by the bending out of the tangs.If the side edges of the tangs were parallel these would not fit into the recesses of the underlying blade.

The clamping member can be an individual catcher, a part of the cylinder head or of the cylinder of the compressor, or an individual fixing part. In the case where the part is a catcher, this is likewise held in the correct position by the projections with which it is provided.

The projections on the clamping member can be formed as noses, which engage in contours of the blade which match therewith and in the depressions of the valve seat. The construction is particularly suited for blade valves with an individual catcher, as thereby the catcher also is secured directly in its position. Furthermore it is not necessary to bend projections out of the blade itself.

The invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is an axial section through the upper part of a typical compressor provided with a blade valve; Fig. 2 is a plan view of a blade for a valve according to the invention Fig. 3 is a longitudinal section of a valve, with the blade of Fig. 2, in the fixing region; Fig. 4 is a longitudinal section of a second embodiment; and Fig. 5 is a plan view of the associated blade of the second embodiment.

As shown in Fig. 1, a plate-shaped valve seat 3 is clamped between the cylinder 1 and the cylinder head 2 of a compressor, with interposition of gaskets 4 and 5. In the valve seat 3 there is provided a through opening 6 for the suction valve and a through opening 7 for the pressure valve.

The opening 6 is covered by a suction blade 8 and the opening 7 by a pressure blade 9.

For limitation of the stroke, the cylinder 1 is provided with a recess 10, into which the end of the suction blade 8 penetrates; and an integrally cast abutment 11 is provided on the cylinder head 2, which abutment lies at an appropriate separation above the pressure blade 9.

For location of the blades 8, 9 relative to the associated through openings 6, 7 in the valve seat 3, there is arranged in this latter, in the region of the fixing position of each blade, a respective depression 12, 13. These depressions may be stamped out, for example, during the preparation of the valve seat 3, thus rendering machining thereof, which would be disadvantageous, unnecessary. Proiections 14 proiect into the depressions 12 and 13, which proiections, in the embodiment of Figs. 2 and 3, are formed as tangs and are bent out of the planes of the blades 8, 9.

Fig. 2 shows the pressure blade 9 of a valve. This is provided, in the neighbourhood of its fixed end, with a circular opening 15, from which radiate incisions 16 in an approximately radial direction. The tangs which are formed between each pair of incisions 16 are bent out of the plane of the blade 9 to form projections 14. As can be further seen from Fig. 2, the incisions 16 which lie on both sides of the projections 14 do not run parallel to each other, but make a slight acute angle a so that the width of each projection 14 tapers in the radially inwards direction towards its free end. In this way, several blades 9 can be stacked, without the side edges of the projections 14 of the upper blades coming into abutment with the side edges of the incision 16 of the lower blades.

Fig. 3 shows how two flexible blades 9 are clamped on the valve seat 3, one upon the other. Projections 14 are bent out from these blades 9 and the blades lie one upon the other and their projections 14 together project into a depression 13 of the valve seat 3. Over the two blades 9 is located an individual clamping member 17, which, with the aid of a screw 18, clamps the ends of the blades 9 onto the valve seat 3. Projections 19 similar to projections 14 of the blades 9 are bent out of the member 17, which projections 19 hold the projections 14 in the depression 13. If projections 14 of the blades 9 are radially arranged, as is shown for example in Fig. 2, three depressions 13 are also provided, in a similar arrangement. There may however be provided only one projection 14 with an associated depression.In the case of several projections, these may be arranged, with the associated depressions, in arbitrary positions on the blade 9, for example in a row next to or behind one another. Also the angle, through which the projections 14 are bent out of the plane of the blade 9, can be chosen within wide limits, without impairment of the task of location which is assigned to the projections.

The blade valve according to Fig. 4 and Fig. 5 is also provided with a valve seat 3 with a through opening 7 and a flexible blade 9, whose form is shown in Fig. 5.

Additionally there is provided a catcher 20, which is fixed to the valve seat 3 together with the blade 9 by means of a screw 21.

The catcher 20 is bent progressively away from the position of fixing from the valve seat 1 in an upwards direction, so. that the blade 9 can perform a relatively large stroke over the through opening 7. As shown in Fig. 4, the catcher 20 is provided, around the screw 21, with projections, which are formed as noses 22 and by their ends project into depressions 13 which are arranged in the valve seat 3 around the screw 21.

In the blade 9 is provided a circular open ing 23 with radial cut-outs 24, which exactly correspond to the noses 22 of the catcher 20. In this way, both the blade 9 and the catcher 20 are secured in their position on the valve seat 3 with the aid of the noses 22 and the depressions 13. In this embodiment too, the necessary tolerances can be observed without any problems.

WHAT WE CLAIM IS:- 1. A blade valve for a compressor, the valve comprising a valve seat having a through opening to be closed by a flexible blade valve member which is clamped at one end to the seat by a clamping member which lies over the blade and is rotationally fast with the blade, the seat having at least one depression in the area where the blade is clamped, and the blade being held in place by at least one projection on the clamping member which projects into said at least one depression.

2. A blade valve according to claim 1, characterized in that the blade is also provided with projections which consist of tangs bent out of the plane of the blade to project into the depressions of the valve seat.

3. A blade valve according to claim 2, characterized in that the width of the tangs tapers, and is narrower at their free ends.

4. A blade valve according to claim 1, characterized in that the clamping member is a catcher, associated with the blade, which includes projections which project through corresponding apertures in the blade, to hold the blade rotationally fast with the clamping member, and are received in the depressions of the valve seat.

5. A blade valve substantially as herein described with reference to and as shown in Figures 2 and 3 or Figures 4 and 5 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ing 23 with radial cut-outs 24, which exactly correspond to the noses 22 of the catcher 20. In this way, both the blade 9 and the catcher 20 are secured in their position on the valve seat 3 with the aid of the noses 22 and the depressions 13. In this embodiment too, the necessary tolerances can be observed without any problems. WHAT WE CLAIM IS:-

1. A blade valve for a compressor, the valve comprising a valve seat having a through opening to be closed by a flexible blade valve member which is clamped at one end to the seat by a clamping member which lies over the blade and is rotationally fast with the blade, the seat having at least one depression in the area where the blade is clamped, and the blade being held in place by at least one projection on the clamping member which projects into said at least one depression.