Noise reduction system

• US 4,043,008 A
• Filed: 09/08/1976
• Issued: 08/23/1977
• Est. Priority Date: 09/08/1976
• Status: Expired due to Term

• Current Assignee: Allied Chemical Corporation (Honeywell International Inc.)
• Original Assignee: Allied Chemical Corporation (Honeywell International Inc.)
• Inventors: Cooksey, James Judson, Weiss, William Robert, Mullins, Phillip Leroy
• Primary Examiner(s): Rimrodt, Louis K.
• Application Number:
  US05/721,262
• Time in Patent Office: 349 Days
• Field of Search: 28/1.4, 28/72.12, 28/71.3, 28/240, 28/245, 28/246, 28/271, 28/272, 226/7, 226/97, 181/33 R, 181/33 C, 181/33 G, 181/33 K, 425/72, 425/211
• US Class Current: 28/271
• CPC Class Codes: D02G 1/161 yarn crimping air jets

Abstract

A noise reduction system is disclosed for use with a draw point localizing jet which has yarn passages, a string-up slot, and conduits for admitting treating fluid thereinto. The system comprises an exhaust muffler and access slot silencing means. The exhaust muffler comprises a housing lined with removable inserts of heat resistant, metallic sound absorbing material. The exhaust muffler has a hinged door operating in conjunction with the access slot silencing means. The muffler and access slot silencing means open and close for string-up and operation. The system lowers the overall noise level of the jet by muffling the noise sources during operation.

Claims

1. In combination with a draw point localizing jet wherein advancing yarn is subjected to pressurized, superheated fluid flow, and wherein said draw point localizing jet has at least one yarn passage passing therethrough and defining yarn entrance and exit ends thereof, said yarn passage having an adjacent access slot to facilitate string-up and having at least one fluid conduit per yarn passage for admitting treating fluid thereinto, the improvements comprising:

A. an exhaust muffler, said muffler comprising;

i. a boxlike metal housing, said housing being located at said exit end of said jet, one corner of said housing being hinged so as to provide a door which pivots to an open position for access to said jet during string-up and to a closed position for treatment during operation, said door being located on the side of said housing corresponding to the side of said jet having said access slot therein, said housing comprising two chambers separated by baffle means connected to and extending inward from the exit of said housing towards said exit end of said jet, said baffle means extending to a point just short of said jet exit so that a gap is left between said baffle means and said exit end of said jet, said gap providing a sight line for an operator, the first of said chambers substantially surrounding said exit end of said jet and surrounding said yarn to a point downstream thereof and with an opening for passage of yarn therethrough, the second of said chambers being positioned contiguous to said first chamber;

ii. means for mounting said housing on said jet;

iii. two metal sound absorbing inserts, said inserts comprising a metal frame, a metallic honeycomb sheet, a sintered metal sheet, a perforated metal sheet, and means for sandwiching these elements, the first of said inserts having a U-shape and being mounted opening towards said door in said first chamber, the second of said inserts having a shape corresponding to the interior portion of said door and being mounted thereon, said inserts being adapted for removable connection to said housing and said interior portion of said door so as to line said first chamber without blocking the passage of said yarn therethrough, said metal frame of said inserts being adjacent said housing and said perforated metal sheet being furthest away from said housing, said honeycomb sheet being adjacent said frame, said sintered metal sheet being adjacent said perforated metal sheet, the cells of said honeycomb sheet opening in a plane transverse to that of said yarn passage if extended through said first chamber, the distance between said sintered metal sheet and said metal frame which is occupied by said honeycomb sheet being approximately 0.25 sound wavelength which corresponds to sound frequencies of 8,000 and 16,000 cycles per second, the open area of said perforated metal sheet ranging from 30 to 45%;

iv. means for mounting said inserts to said walls defining said first chamber and to said interior of said door, and

B. access slot silencing means, said access slot silencing means comprising a projection of said housing, a mounting plate, a silencing plate, a pin, and a compression spring, said projection being an extension of said housing door in the direction of said jet entrance, said projection pivoting with said door into an open and a closed position, said projection blocking access to said side of said jet having said access slot therein when in said closed position, said projection having said mounting plate spaced therefrom and attached thereto on the side closer to said jet when in said closed position, said mounting plate having a slot with said pin passing therethrough, said pin being connected on the end located closer to said jet to said silencing plate and being connected at its other end to stopping means which prohibits its passing completely through said slot, said compression spring surrounding the portion of said pin located between said projection and said slot, said silencing plate corresponding in length and being slightly wider than said access slot in said jet;

whereby the noise level of said jet is changed from a continuous source to an intermittent source, emitting high level noise only during string-up and alignment, by;

(1) the automatic closure of said access slot by said silencing plate when said jet is operational and said projection is pivoted along with said housing door to within 1.5 inches of said access slot, said closure resulting from the vacuum-like action induced by said treating fluid; and

(2) the closure of said access slot simultaneously closing said housing door to close said first chamber of said exhaust muffler thereby reducing noise at the yarn exit, and whereby the noise level of said jet is reduced by up to 16 ±

1.5 Δ

dB(A) when said housing door and said projection are in said closed position.

2. Apparatus as defined in claim 1 wherein the sides of said jet have an asbestos-free insulating material secured thereto which does not interfere with their operation and wherein said means for mounting said housing on said jet comprises a flange which extends downwardly from said housing on the sides of said jet other than said side having said access slot therein and which is adapted for connection to said insulating material by suitable means to thereby preclude any contact between said jet and said housing.

3. The apparatus of claim 2 wherein said insulating material is a compressed mineral wool.

4. A noise reduction system for use in conjunction with a yarn treating jet, said jet having at least one yarn passage therethrough defining yarn entrance and exit ends thereof, said yarn passage having an adjacent access slot to facilitate string-up and having at least one fluid conduit per yarn passage for admitting treating fluid thereinto, said noise reduction system comprising:

A. an exhaust muffler, said muffler comprising;

i. a metal housing, said housing being located at and substantially surrounding said exit end of said jet and substantially surrounding said yarn to a point downstream thereof and with an opening for passage of yarn therethrough, a portion of said housing being movable and functioning as a door which pivots to an open position for access to said jet during string-up and to a closed position for treatment during operation;

ii. pivot means, said pivot means connecting said housing and said portion thereof which functions as said door;

iii. means for mounting said housing on said jet;

iv. a metal sound absorbing liner, said liner comprising a plurality of contiguous resonant chambers, a sintered metal sheet, and a perforated metal sheet, said liner being adapted for connection to the interior of said housing without interfering with the pivotal movement thereof and without blocking the passage of said yarn therethrough, said resonant chambers being adjacent said housing and said perforated metal sheet being furthest away from said housing, said resonant chambers opening in a plane transverse to that of said yarn passage if extended through said housing; and

v. means for mounting said liner to said interior of said housing; and

B. access slot silencing means, said access slot silencing means comprising a projection of said housing, an extensible member and closure means, said projection being an extension of said housing door in the direction of said jet entrance, said projection pivoting with said door into an open and a closed position, said projection having said extensible member mounted thereon on the side closer to said jet when in said closed position, said extensible member having said closure means attached thereto on the end closer to said jet when said projection is in said closed position, said closure means being shaped so as to block said access slot of said jet when brought into proximate relationship therewith;

whereby the noise level of said jet is changed from a continuous source to an intermittent source, emitting high noise level only during string-up, by the automatic closure of said access slot and said exhaust muffler by said closure means when said jet is operational and said projection is pivoted along with said housing door towards said access slot, said closure resulting from the vacuum-like action induced on said closure means and said extensible member by said treating fluid, and whereby the noise level of said jet is reduced by up to 16 ±

1.5 Δ

dB(A) when said housing door and said projection are in said closed position.

5. Apparatus as defined in claim 4 wherein the sides of said jet have an asbestos-free insulating material secured thereto which does not interfere with their operation and wherein said means for mounting said housing on said jet comprises a flange which extends downwardly from said housing on the sides of said jet other than said side having said access slot therein and which is adapted for connection to said insulating material to thereby preclude any contact between said jet and said housing.

6. The apparatus of claim 5 wherein said insulating material is a compressed mineral wool.

7. Apparatus as defined in claim 4 wherein said housing comprises two chambers separated by baffle means connected to and extending inward from the exit of said housing towards said exit end of said jet, said baffle means extending to a point just short of said jet exit so that a gap is left between said baffle means and said exit end of said jet, said gap providing a sight line for an operator, the first of said chambers substantially surrounding said exit end of said jet and surrounding said yarn to a point downstream thereof and with an opening for passage of yarn therethrough, the second of said chambers being positioned contiguous to said first chamber, said metal sound absorbing liner being removably mounted to the interior of said first chamber.

8. Apparatus as defined in claim 4 wherein the distance between said sintered metal sheet and said interior of said housing which is occupied by said contiguous resonant chambers is approximately 0.25 sound wavelength, which corresponds to sound frequencies of 8,000 and 16,000 cycles per second.

9. Apparatus as defined in claim 4 wherein the open area of said perforated metal sheet ranges from 30 to 45%.

10. Apparatus as defined in claim 4 wherein a metallic honeycomb sheet forms said plurality of contiguous resonant chambers.

11. Apparatus as defined in claim 4 wherein the elements of said liner are sandwiched together to form inserts which are adapted for removable connection to the interiors of, respectively, said portion of said housing functioning as a door and the remainder of said housing substantially surrounding said yarn to a point downstream of said exit end of said jet, and wherein means is provided for mounting said inserts to their respective portions of said interior of said housing.

12. Apparatus as defined in claim 4 wherein said jet is a draw point localizing jet.

13. Apparatus as defined in claim 4 wherein said housing is substantially rectangular in shape.

14. Apparatus as defined in claim 4 wherein said projection has a mounting plate spaced therefrom and attached thereto on the side closer to said jet when in said closed position, said mounting plate having a slot therethrough, and wherein said extensible member comprises a pin and a compression spring, said closure means comprising a silencing plate, said pin passing through said slot in said mounting plate, said pin being connected on the end located closer to said jet to said silencing plate and being connected at its other end to stopping means which prohibits its passing completely through said slot, said compression spring surrounding the portion of said pin located between said projection and said slot, said silencing plate corresponding in length and being slightly wider than said access slot in said jet.

15. In combination with a draw point localizing jet wherein advancing yarn is subjected to pressurized, superheated fluid flow, and wherein said draw point localizing jet has at least one yarn passage passing therethrough and defining yarn entrance and exit ends thereof, said yarn passage(s) having at least one fluid conduit per yarn passage for admitting treating fluid thereinto, the improvement comprising an exhaust muffler, said muffler comprising:

A. a boxlike metal housing, said housing being located at said exit end of said jet, one corner of said housing being hinged so as to provide a door which pivots to an open position for access to said jet during string-up and to a closed position for treatment during operation, said housing comprising two chambers separated by baffle means connected to and extending inward from the exit of said housing towards said exit end of said jet, said baffle means extending to a point just short of said jet exit so that a gap is left between said baffle means and said exit end of said jet, said gap providing a sight line for an operator, the first of said chambers substantially surrounding said exit end of said jet and surrounding said yarn to a point downstream thereof and with an opening for passage of yarn therethrough, the second of said chambers being positioned contiguous to said first chamber;

B. a latching mechanism for holding said door in said closed position;

C. means for mounting said housing on said jet;

D. two metal sound absorbing inserts, said inserts comprising a metal frame, a metallic honeycomb sheet, a sintered metal sheet, a perforated metal sheet, and means for sandwiching these elements, the first of said inserts having a U-shape and being mounted opening towards said door in said first chamber, the second of said inserts having a shape corresponding to the interior portion of said door and being mounted thereon, said inserts being adapted for removable connection to said housing and said interior portion of said door so as to line said first chamber without blocking the passage of said yarn therethrough, said metal frame of said inserts being adjacent said housing, said metallic honeycomb being adjacent said frame, said sintered metal sheet being adjacent said perforated metal sheet, said perforated metal sheet being furthest away from said housing, the cells of said honeycomb sheet opening in a plane transverse to that of said yarn passage if extended through said first chamber, the distance between said sintered metal sheet and said metal frame which is occupied by said honeycomb sheet being approximately 0.25 sound wavelength which corresponds to sound frequencies of 8,000 and 16,000 cycles per second, the open area of said perforated metal sheet ranging from 30 to 45%; and

E. means for mounting said inserts to said walls defining said first chamber;

whereby the noise level of said jet is reduced when said door is in said closed position.

16. Apparatus as defined in claim 15 wherein the sides of said jet have an asbestos-free insulating material secured thereto which does not interfere with their operation and wherein said means for mounting said housing on said jet comprises a flange which extends downwardly from said housing on the sides of said jet and which is adapted for connection to said insulating material by suitable means to thereby preclude any contact between said jet and said housing.

17. The apparatus of claim 16 wherein said insulating material is a compressed mineral wool.

18. A muffler for use in conjunction with a yarn treating jet, said jet having at least one yarn passage therethrough defining yarn entrance and exit ends thereof, said muffler comprising:

A. a metal housing, said housing being located at and substantially surrounding said exit end of said jet and substantially surrounding said yarn to a point downstream thereof and with an opening for passage of yarn therethrough;

B. means for mounting said housing on said jet;

C. a metal sound absorbing liner, said liner comprising a plurality of contiguous resonant chambers, a sintered metal sheet, and a perforated metal sheet, said liner being adapted for connection to the interior of said housing without blocking the passage of said yarn therethrough, said resonant chambers being adjacent said housing and said perforated metal sheet being furthest away from said housing, said resonant chambers opening in a plane transverse to that of said yarn passage if extended through said housing; and

D. means for mounting said liner to said interior of said housing;

whereby the noise level of said jet is reduced by said muffler.

19. Apparatus as defined in claim 18 wherein the distance between said sintered metal sheet and said interior of said housing which is occupied by said contiguous resonant chambers is approximately 0.25 sound wavelength, which corresponds to sound frequencies of 8,000 and 16,000 cycles per second.

20. Apparatus as defined in claim 18 wherein the open area of said perforated metal sheet ranges from 30 to 45%.

21. Apparatus as defined in claim 18 wherein a metallic honeycomb sheet forms said plurality of contiguous resonant chambers.

22. Apparatus as defined in claim 18 wherein the elements of said liner are sandwiched together to form an insert which is adapted for removable connection to said interior of said housing and wherein means is provided for mounting said insert thereto.

23. Apparatus as defined in claim 18 wherein the sides of said jet have an asbestos-free insulating material secured thereto which does not interfere with their operation and wherein said means for mounting said housing on said jet comprises a flange which extends downwardly from said housing on the sides of said jet and which is adapted for connection to said insulating material by suitable means to thereby preclude any contact between said jet and said housing.

24. The apparatus of claim 23 wherein said insulating material is a compressed mineral wool.

25. Apparatus as defined in claim 18 wherein a portion of said housing is movable and functions as a door which pivots to an open position for access to said interior thereof, pivot means and a latching mechanism also being provided, said pivot means connecting said housing and said portion thereof which functions as said door, said latching mechanism holding said housing in a closed position.

26. Apparatus as defined in claim 25 wherein said housing comprises two chambers separated by baffle means connected to and extending inward from the exit of said housing towards said exit end of said jet, said baffle means extending to a point just short of said jet exit so that a gap is left between said baffle means and said exit end of said jet, said gap providing a sight line for an operator, the first of said chambers substantially surrounding said exit end of said jet and surrounding said yarn to a point downstream thereof and with an opening for passage of yarn therethrough, the second of said chambers being positioned contiguous to said first chamber, said metal sound absorbing liner being removably mounted to the interior of said first chamber.

27. In combination with a draw point localizing jet wherein advancing yarn is subjected to pressurized, superheated fluid flow, and wherein said draw point localizing jet has at least one yarn passage passing therethrough and defining yarn entrance and exit ends thereof, said yarn passage having an adjacent access slot to facilitate string-up and having at least one fluid conduit per yarn passage for admitting treating fluid thereinto, the improvement of access slot silencing means which comprises:

A. a first support plate, said first support plate being connected by suitable means to one of the sides of said jet adjacent the side having said access slot therein;

B. a second support plate, said second support plate being hinged to said first support plate so as to permit its pivoting into an open and a closed position, said second support plate blocking access to said side of said jet having said access slot therein when in said closed position;

C. a mounting plate, said second support plate having said mounting plate spaced therefrom and attached thereto on the side closer to said jet when in said closed position, said mounting plate having a slot therethrough which approximately faces said access slot when said second support plate is in said closed position;

D. a pin, said pin passing through said slot in said mounting plate;

E. a silencing plate, said silencing plate corresponding in length and being slightly wider than said access slot in said jet and being connected to the end of said pin located closer to said jet;

F. stopping means, said stopping means being connected to the other end of said pin and functioning to prohibit the passage of said pin completely through said slot; and

G. a compression spring, said compression spring surrounding the portion of said pin located between said projection and said slot;

whereby the noise level of said jet is reduced by up to 4.5 Δ

dB(A) by automatic closure of said access slot by said silencing plate when said jet is operational and said second support plate is pivoted to within 1.5 inches of said access slot, said closure resulting from the vacuum-like action induced by said treating fluid.

28. In combination with a yarn treating jet wherein advancing yarn is subjected to pressurized fluid flow, and wherein said jet has at least one yarn passage therethrough which has an adjacent access slot to facilitate string-up and which has at least one fluid conduit per yarn passage for admitting treating fluid thereinto, the improvement of access slot silencing means which comprises:

A. mounting means;

B. support means, said support means having pivot means thereon adapted for connection to said mounting means and about which said support means can pivot into an open position during string-up of said jet and a closed position during treatment;

C. an extensible member, said extensible member being mounted on the side of said support means which is closer to said jet when said support means is in said closed position; and

D. closure means, said closure means being attached to said extensible member on the end closer to said jet when said support means is in said closed position, said closure means being shaped so as to block said access slot of said jet when brought into proximate relationship therewith;

whereby operation of said jet creates an atmosphere of suction at said access slot which pulls said closure means via extension of said extensible member to close said access slot and bring said support means into said closed position when said support means is pivoted towards said access slot.