What is claimed:
1. A scroll fluid machine with multi-stage compression section in which the fluid compressed in the preceding stage compression section is further compressed in the succeeding stage compression section characterized in that:
a lap groove is formed spiraling from the vicinity of the discharge port of the compressed fluid of the final stage compression space to the fluid take-in side of the initial stage compression space, in the tip of the lap being formed a tip seal grove to receive a seal element, and a rand is formed between the discharge port at the compression end part of said preceding stage compression section and the suction port of the succeeding stage compression section; and
an intermediate seal element is received in the intermediate groove formed on the surface of said rand which faces the end plate of the mating scroll for preventing the leakage of the compressed fluid from said succeeding stage compression section to said discharge port opening side of said preceding stage compression section.
2. A scroll fluid machine with multi-stage compression section according to claim 1 characterized in that said seal element consists of;
a tip seal received in the groove formed in the tip of the spiral lap of both side forming said lap groove, and
an intermediate seal element located between said discharge port opening and said suction port opening.
3. A scroll fluid machine with multi-stage compression section according to claim 2 characterized in that,
said intermediate seal element is a circular seal element partitioning said succeeding stage compression section circularly.
4. A scroll fluid machine with multi-stage compression section according to claim 1 characterized in that said seal element consists of;
a first seal element which extends spirally from the fluid take-in side of said preceding stage compression section side to the final discharge port side of said succeeding stage compression section and partitions said discharge port opening and said suction port opening at said rand surface in the course of its extension, and
a second seal element, an end of which contacts the side face of said first seal element at the side opposite to said discharge port opening in the vicinity of said discharge port opening and which extends from the vicinity of said discharge port opening to the vicinity of said discharge port opening, surrounding said succeeding stage compression section to contact the side face of said first seal element at the side opposite to said suction port opening.
5. A scroll fluid machine with multi-stage compression section according to claim 1 characterized in that:
a tip seal groove is formed extending spirally from the fluid take-in side of said initial stage compression section toward the compressed fluid discharge port side of said final stage compression space,
an intermediate groove is formed communicating with said tip seal groove in said rand between said discharge port opening and said suction port opening,
a set of seal elements consisting of a plurality of seal elements is received in said intermediate groove and said tip seal groove,
said seal set consists of;
a first tip seal which extends from the compressed fluid discharge port side of said final stage compression space toward said initial stage compression space via said intermediate groove,
a second tip seal which extends parallel with said first tip seal from the compressed fluid discharge port side of said final stage compression space to the vicinity of said suction port opening where the second tip seal depart from said first tip seal and contacts said first seal in the vicinity of said discharge port opening, and
a third tip seal which extends in said tip groove parallel with said second tip seal from the vicinity of said suction port opening to partition said succeeding stage compression section circularly and further extends parallel with said first tip seal toward said initial stage compression section side.
6. A scroll fluid machine with multi-stage compression section according to claim 1 characterized in that:
a tip seal groove is formed extending spirally from the fluid take-in side of said initial stage compression section toward the compressed fluid discharge port side of said final stage compression space,
an intermediate groove is formed communicating with said tip seal groove in said rand between said discharge port opening and said suction port opening, and
said seal element is a single tip seal received in said tip seal groove and said intermediate groove.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-11. (canceled)
12. An apparatus for blending of a Digital Audio Broadcast transmission first audio signal and a Frequency Modulated transmission second audio signal comprising:
a first receiver receiving a Digital Audio Broadcast transmission;
a first demodulator connected to said first receiver producing a first left audio signal and a first right audio signal from said received Digital Audio Broadcast transmission;
a second receiver receiving a Frequency Modulated transmission;
a second demodulator connected to said second receiver producing a second left audio signal and a second right audio signal from said received Frequency Modulated transmission;
a quality of service unit connected to said first receiver, said first demodulator, said second receiver and said second demodulator, said quality of service unit producing a first quality of service indication for said received Digital Audio Broadcast transmission and a second quality of service indication for said received Frequency Modulated transmission; and
a blending unit receiving said first left audio signal and said first right audio signal from said first demodulator, said second left audio signal and said second right audio signal from said second modulator and said first quality of service indication and said second quality of service indication from sais quality of service unit, said blending unit operable to
calculate an average envelop value of the first audio said over a time span Ts as follows:
DAB audio=DAB_Left+DAB_Right
DAB_envelope=ABSDAB_audio, and
DAB_Envelope_Avg=(1\u2212\u03b1)*DAB_Envelope_Avg+\u03b1*DAB_envelope
where: DAB_Left is said left channel of said first audio signal; DAB_Right is said right channel of said first audio signal; and \u03b1 is selected whereby Ts*(1\u2212\u03b1)\u03b1\u02dc0.1;
downsample the average envelop value of said first audio signal;
calculate an average envelop value of said second audio signal over the time span Is as follows:
FM_audio=FM_LpR
FM_envelope=ABSFM_audio
FM_Envelope_Avg=(1\u2212\u03b1)*FM_Envelope_Avg+\u03b1*FM_envelope
where: FM_Left is said left channel of said second audio signal; and FM_Right is said right channel of said second audio signal;
downsample the average envelop value of said second audio signal;
calculate a first gain adjustment for said first audio signal;
calculate a second gain adjustment for said second audio signal;
apply gain adjustment to said second audio signal;
calculate a time delay between said first audio signal and said second audio signal; and
blend said first audio signal and said second audio signal offset by said calculated time delay based upon said first Quality of Service indication and said second Quality of Service indication.
13. The apparatus of claim 12 further comprising:
a first circular buffer connected to said first demodulator to buffer said first audio signal;
a second circular buffer connected to said second demodulator to buffer said second audio signal; and
wherein said first and second circular buffers have sufficient length to hold signals during a worse case time delay.
14. The apparatus of claim 12, wherein:
said blending unit is further operable to calculate said first gain adjustment as follows:
DAB_Envelope_Level=(1\u2212\u03b2)*DAB_Envelope_Level+\u03b2*DAB_envelope_Avg
where: \u03b2 is selected whereby Ts*10*(1\u2212\u03b2)\u03b2\u02dc1.0.
15. The apparatus of claim 12, wherein:
said blending unit is further operable to calculate said second gain adjustment as follows:
FM_Envelope_Level=(1\u2212\u03b2)*FM_Envelope_Level+\u03b2*FM_envelope_Avg
where: \u03b2 is selected whereby Ts*10*(1\u2212\u03b2)\u03b2\u02dc1.0.
16. The apparatus of claim 12, wherein:
said blending unit is further operable to apply gain adjustment to the second audio signal operates as follows:
FM_Gain_Adj=(DAB_Envelope_Level)(FM_Envelope_Level),
FM_audio=FM_Gain_Adj*FM_audio.
17. The apparatus of claim 12, wherein:
said blending unit is further operable to calculate said time delay between the first audio signal and the second audio signal includes as follows:
calculate a correlation for each value k from a worse case time delay to 0:
Audio_Corr=\u03a3KFM_Envelope_Avgn*DAB_Envelope_Avgn\u2212k;
determine a value k yielding a maximum Audio_Corr; and
determine the time delay corresponding to the value k yielding the maximum Audio_Corr.
18. The apparatus of claim 12, wherein:
said blending unit is further operable to blend the first audio signal and the second audio signal offset by the calculated time delay as follows
set a minimum acceptable Quality of Service indicator thresholds for said first audio signal and said second audio signal,
select a preferred audio signal as follows:
if DAB_QOS<either threshold,
then DAB_FM_Blend=FM offset by time delay k,
else DAB_FM_Blend=DAB.