1. A flow control device for use with a pulse detonation chamber, said device comprising:
an inlet coupled in flow communication with a source of compressed air, said inlet extending at least partially into the chamber to facilitate controlling air flow into the chamber; and
a body portion extending downstream from and circumferentially around said inlet, said body portion positioned in flow communication with said inlet.
2. A device in accordance with claim 1 wherein said inlet is coupled within the chamber such that a pre-determined circumferential gap is defined between said inlet and said body portion for fixedly controlling air flow into the chamber.
3. A device in accordance with claim 2 wherein said inlet portion comprises a converging nozzle coupled to a chamber inlet portion, said nozzle includes an outlet formed for fixedly controlling air flow into the chamber.
4. A device in accordance with claim 1 wherein said inlet is variably adjustable within the chamber to facilitate changing a circumferential gap defined between said inlet and said body portion.
5. A device in accordance with claim 1 wherein said body portion comprises a substantially convergent diameter for at least a portion thereof.
6. A device in accordance with claim 1 wherein said body portion comprises a first portion comprising a substantially convergent diameter and a second portion comprising a substantially divergent diameter.
7. A device in accordance with claim 1 wherein said body portion comprises a first portion comprising a substantially convergent diameter and a second portion comprising a partially divergent diameter.
8. A pulse detonation engine comprising:
a compressor configured to compress air therein;
a pulse detonation combustor coupled to an axial turbine including at least one pulse detonation chamber comprising an inlet portion, an outlet portion, and a body portion extending therebetween, said inlet portion coupled in flow communication with said compressor for receiving compressed air therethrough, said chamber comprising:
a fuel injector for supplying fuel to said chamber;
a detonation device coupled to said chamber for initiating a detonation wave within said chamber; and
a flow control device comprising an inlet for controlling air flow into said at least one pulse detonation chamber and a body portion coupled in flow communication with said inlet.
9. An engine in accordance with claim 8 wherein said air inlet portion is fixedly secured within said chamber such that a pre-determined gap is defined circumferentially between said air inlet portion and said body portion, said gap facilitates controlling air flow into said chamber.
10. An engine in accordance with claim 9 wherein said inlet comprises a converging nozzle coupled to said chamber inlet portion and comprising a port formed for fixedly controlling air flow into said chamber.
11. An engine in accordance with claim 8 wherein said inlet portion is adjustably coupled within said chamber such that said circumferential gap is variable to facilitate selectively controlling air flow into said chamber.
12. An engine in accordance with claim 8 wherein said body portion comprises a substantially convergent diameter for at least a portion thereof.
13. An engine in accordance with claim 8 wherein said body portion comprises a first portion comprising a substantially convergent diameter and a second portion comprising a substantially divergent diameter.
14. An engine in accordance with claim 8 wherein said body portion comprises a first portion comprising a substantially convergent diameter and a second portion comprising a partially divergent diameter.
15. A method for adjusting air flow through a pulse detonation combustor, said method comprising:
providing at least one pulse detonation chamber including an inlet portion, an outlet portion, and a body portion extending therebetween;
coupling an inlet within the chamber inlet portion and in flow communication with a source of compressed air for controlling air flow into the at least one pulse detonation chamber; and
coupling a body portion downstream from and circumferentially around the chamber inlet portion and in flow communication with the inlet.
16. A method in accordance with claim 15 wherein coupling an inlet within the chamber inlet portion further comprises coupling the inlet within the chamber such that a pre-determined circumferential gap is defined between the inlet and the body portion to facilitate controlling air flow into the chamber.
17. A method in accordance with claim 15 wherein coupling an inlet within the chamber inlet portion further comprises variably coupling the inlet within the chamber to facilitate changing a circumferential gap defined between the inlet and the body portion.
18. A method in accordance with claim 15 wherein coupling a body portion downstream from and circumferentially around the chamber inlet portion further comprises coupling the body portion comprising a substantially convergent diameter for at least a portion thereof.
19. A method in accordance with claim 15 wherein coupling a body portion downstream from and circumferentially around the chamber inlet portion further comprises coupling the body portion comprising a first portion comprising a substantially convergent diameter and a second portion comprising a substantially divergent diameter.
20. A method in accordance with claim 15 wherein coupling a body portion downstream from and circumferentially around the chamber inlet portion further comprises coupling the body portion comprising a first portion comprising a substantially convergent diameter and a second portion comprising a partially divergent diameter.
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. A drum brake apparatus comprising:
a first and a second brake shoes disposed in a drum to oppose each other; and
a cam mechanism for generating a braking force by opening the first and second brake shoes outward according to a shoe operating force generated by an operating force generator, and for controlling the braking force by utilizing a reaction force exerted from the brake shoes during a braking period,
wherein the cam mechanism includes:
a cam supporting plate, having a central circular aperture portion is continuous with two opposed circular aperture portions, loosely and rotatably fitted on an anchor pin projecting upright on a backing plate, and having an input power receiving portion for receiving the shoe operating force at a position radially inwardly of the drum with respect to the anchor pin;
a first cam plate, rotatably connected to the cam supporting plate at an outer cam supporting position which is located radially outwardly of the drum with respect to the anchor pin, and having a first shoe receiving arcuate portion which comes into abutment with an end of one of the brake shoes; and
a second cam plate, rotatably connected to the cam supporting plate at an inner cam supporting position along a point between the anchor pin and the input power receiving portion, and having a second shoe receiving arcuate portion which comes into abutment with the end of the other brake shoe.
2. The drum brake apparatus according to claim 1, wherein the first cam plate and the second cam plate respectively comprise an anchor abutting arcuate portion rotatably slidable against the outer periphery of the anchor pin, further comprising:
a damper spring for alleviating an impact applied when each anchor abutting arcuate portion comes into abutment with the outer periphery of the anchor pin when controlling a torque.
3. The drum brake apparatus according to claim 1, further comprising a strut, for opening one of the brake shoes by being displaced toward the one of the brake shoes when the operating force is fed from a parking lever, provided in a vacant space between the second cam plate and the input power receiving portion.
4. The drum brake apparatus according to claim 3, wherein the strut includes a guide groove extending in the direction of displacement caused by braking, and is supported by the cam supporting plate so as to be capable of moving along the direction of displacement caused by braking, by inserting a guide pin provided upright on the cam supporting plate into the guide groove.
5. The drum brake apparatus according to claim 3, further comprising a resilient member for maintaining abutment between the strut for the parking brake and the parking lever.
6. The drum brake apparatus according to claim 1, further comprising a resilient clip for retaining the first cam plate, the second cam plate, and the cam supporting plate in the assembled state.
7. The drum brake apparatus according to claim 1, wherein the input power receiving portion of the cam supporting plate includes a supporting shaft, which comes into abutment with the output end of the operating force generator, engaged and supported by a notch formed on the cam supporting plate.
8. The drum brake apparatus according to claim 1,
wherein the first cam plate is rotatably connected to the cam supporting plate by a first cam pin fitted to the cam supporting plate at the outer cam supporting position,
the second cam plate is rotatably connected to the cam supporting plate by a second cam pin fitted to the cam supporting plate at the inner cam supporting position,
each cam pin is provided with a positioning shaft passing through the cam supporting plate and projecting toward the root side of the anchor pin, and
the cam supporting plate loosely fitted to the anchor pin is located in the direction of the axis of the anchor pin by abutting the extremity of the positioning shaft of each cam pin against a flange projecting on the root side of the anchor pin.
9. The drum brake apparatus according to claim 8, wherein the extremity of the positioning shaft of the cam pin is formed into a substantially semi-spherical surface.
10. A drum brake apparatus comprising:
a first and a second brake shoes disposed in a drum to oppose each other; and
a cam mechanism for generating a braking force by opening the first and second brake shoes outward according to a shoe operating force generated by an operating force generator, and for controlling the braking force by utilizing a reaction force exerted from the brake shoes during a braking period,
wherein the cam mechanism includes:
a cam supporting plate, loosely and rotatably fitted on an anchor pin projecting upright on a backing plate, and having an input power receiving portion for receiving the shoe operating force at a position radially inwardly of the drum with respect to the anchor pin;
a first cam plate, rotatable connected to the cam supporting plate at an outer cam supporting position which is located radially outwardly of the drum with respect to the anchor pin, and having a first shoe receiving arcuate portion which comes into abutment with an end of one of the brake shoes; and
a second cam plate, rotatable connected to the cam supporting plate at an inner cam supporting position along a point between the anchor pin and the input power receiving portion, an having a second shoe receiving arcuate portion which comes into abutment with the end of the other brake shoe,
wherein, until a shoe clearance is eliminated, the cam supporting plate rotates about one of cam supporting positions of one of the cam plates which receives the brake power, to open the brake shoe being in abutment with the other of cam plates, and
after the shoe clearance is eliminated, the cam supporting plate rotates about the anchor pin to press the first and the second brake shoes against the drum.
11. A drum brake apparatus comprising:
a first and a second brake shoes disposed in a drum to oppose each other; and
a cam mechanism for generating a braking force by opening the first and second brake shoes outward according to a shoe operating force generated by an operating force generator, and for controlling the braking force by utilizing a reaction force exerted from the brake shoes during a braking period,
wherein the cam mechanism includes:
a cam supporting plate, loosely and rotatable fitted on an anchor pin projecting upright on a backing plate, and having an input power receiving portion for receiving the shoe operating force at a position radially inwardly of the drum with respect to the anchor pin;
a first cam plate, rotatable connected to the cam supporting plate at an outer cam supporting position which is located radially outwardly of the drum with respect to the anchor pin, and having a first shoe receiving arcuate portion which comes into abutment with an end of one of the brake shoes; and
a second cam plate, rotatably connected to the cam supporting plate at an inner cam supporting position along a point between the anchor pin and the input power receiving portion, and having a second shoe receiving arcuate portion which comes into abutment with the end of the other brake shoe, wherein the drum brake apparatus, further comprising a swinging movement limiter,
wherein distances L1 and L2 are set to L1\u2260L2, where L1 is a distance between the center of curvature of the first shoe receiving arcuate portion and the center of the anchor pin and L2 is a distance between the center of curvature of the second shoe receiving arcuate portion and the center of the anchor pin, and
wherein the swinging movement limiter limits the range of swinging movement of the respective cam plates, so that only one of the cam plates being smaller in distance between the center of the anchor pin and the center of curvature of the shoe receiving arcuate portion swings integrally with the cam supporting plate, and opens the brake shoes outward until the shoe clearance is eliminated.