US2503417A - Controlling mechanism for sand traps - Google Patents

Controlling mechanism for sand traps Download PDF

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US2503417A
US2503417A US679449A US67944946A US2503417A US 2503417 A US2503417 A US 2503417A US 679449 A US679449 A US 679449A US 67944946 A US67944946 A US 67944946A US 2503417 A US2503417 A US 2503417A
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disk
valve
air
casing
sand
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US679449A
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Frank E Saari
Grant V W Roth
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61CLOCOMOTIVES; MOTOR RAILCARS
    • B61C15/00Maintaining or augmenting the starting or braking power by auxiliary devices and measures; Preventing wheel slippage; Controlling distribution of tractive effort between driving wheels
    • B61C15/08Preventing wheel slippage
    • B61C15/10Preventing wheel slippage by depositing sand or like friction increasing materials
    • B61C15/102Preventing wheel slippage by depositing sand or like friction increasing materials with sanding equipment of mechanical or fluid type, e.g. by means of steam

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  • the main object of the invention is to provide valve-mechanism of this type which include an auxiliary self-closing valve, controlled by the rotative movements of the valve-disk, for automatically cutting off the supply of compressed air to the valve-disk chamber in the casing, and thereby practically eliminating unilateral pressure and reducing drag on the valve-disk for ease of its operation, and also preventing leakage of air from the casing while the valve-disk is set to cut off the delivery of air to the trap, in the event that the casing sections, or the engaging faces of the l,
  • valve-disk and its seat in the casing are imperfectly or defectively fitted, or particles become lodged between said faces.
  • Another object of the invention is to provide a valve of this type which is simple in construction and can be economically produced.
  • Figure 1 is a side elevation of a valve embodying the invention.
  • Figure 2 is a section taken on line 2-4 of ure 1.
  • Figure 3 is a perspective of the rotatable valvedisk.
  • Figure 4 is a section taken on line 4-4 of Figure'2.
  • Figure 5 is a section taken on line 5--5.
  • Figure 6 is a sectionillustrating theauxlliary valve in its open position, to admit the passage of compressed air to the disk valve.
  • valve-mechanism which comprises a casing'formedof outlet and inlet sections Illand II, which are secured together by screws-I2.
  • a pipe I3 leading from a source of compressed air supply, is connected to the section II of the casing.
  • Pipes and I5 are connected to'receive air from separate conduits in the casing-section III, and are connected respectively to the ducts in a pairof sand traps, for delivering clean-out blasts to the sand traps, as well understood in the art.
  • Pipes I6 and H are connected to receive air from separate conduits in casing-section I0, and are connected respectively to deliver air for discharging sand from a pairof traps, as well understoo'dinthe art.
  • a chamber I8,-in the casing is adapted to receive air from supply pipe I3, under control of the auxiliary valve hereinafter described.
  • a valve-disk I9 is rotatable in the chamber I8, and has one of its faces fitting against the face 20 in casin section III, which forms a seat for said disk.
  • Disk I9 is rotatable by a stud 2
  • Stud H has afiixed thereto, a hand lever 23, which is provided with a spring pressed dog 24, adapted to engage a series of notches 26, formed in a segment on the casingsection III, for yieldably holding the lever in its different selective and predetermined positions.
  • a port 21 extends through valve-disk I 9, and controls the flow of air.
  • disk I9 may be rotated toselectively supply air separately to the ducts 28, 29, 30 and 3
  • An auxiliary valve is mounted in the inlet casing-section II, and controls the flow of air from a chamber 34, which is communicatively connected to the air supply pipe I3, through an opening 35, into the chamber I8.
  • Valve 33 comprises a stem 36, whichis slidably mounted in a cap 31, a packing 38 secured on a head 39 by a screw 40,-and a washer III.
  • a spring 42 is adapted to normally close the exposed face of the packing disk 38, against a seat, which surrounds the opening 35.
  • the auxiliary valve is controlled by an arcuate cam 46, which is integral with and projects from, one face of the valve-disk l9, and an arm or lever 43, which is fulcrumed at 44 on the center of disk I9, has a V-shaped corner 45, engaged by cam 46 and an extension or abutment 41, which is adapted to engage a part of valve 33, such as the screw 40, to force valve 33 away from its seat, against the force of spring 42.
  • Lever 23 is confined against rotation with disk IS, in a recess 56 in casing-section ll.
  • Lever 43 is urged toward disk l9 by a spring 48, which is confined in a socket in casing-section II, and exerts pressure against lever 43 for hOldiIlg disk [9 against its seat 20.
  • Cam 46 comprises V-shaped members 49, which are adapted to shift valve 33 to its open position when the disk 19 is rotated in opposite directions, to bring port 21 into registry with ducts 28, 29 respectively, for delivering air for the clean-out blasts, and raised end-portions 50, which are adapted to shift lever 43, to open valve 33, when the disk I9 is rotated to bring port 21 into registry with the ducts 33, 3
  • V-shaped depressions 51 in cam 46 are provided to permit valve 33 to close between the clean-out blasts and the discharge of the sand from the sand traps.
  • disk [9 When disk [9 is in position to cut oil flow of air through port 21, lever 43 engages a central V-shaped depression between members 49, and valve 33 will be closed.
  • valve 33 When valve 33 is in its open position, the pressure of spring 42, urges said valve toward its seat, and will also cause the V-shaped corner 45 of lever 43, to exert pressure on the inclined members of the V-shaped depressions in cam 46 for rotating the valve-disk into its cut-off positions.
  • valve 38 While lever 23 is in its neutral or central position, port 21 will be out of communication with any one of the ducts 28, 29, 30 and 3
  • cam members 49 When lever 23 is shifted to rotate disk I9, and bring port 21 into registry with conduit 28 or 29, for delivering clean-out blasts to the traps, cam members 49 will shift lever 43 so its extension 41 will shift valve 33 against the force of spring 42, and cause air to pass from pipe l3 via chamber 34 and opening 35, into chamber 18, and through port 21, to the selected conduit 28 or 29.
  • lever 23 When lever 23 is shifted and disk [9 is rotated to bring port 21 into registry with either of the conduits 36 or 3
  • the invention exemplifies a controlling mechanism for a sand trap which comprises a rotatable valve-disk with a port therein, for controlling the delivery of sand to the sand traps, and an automatically closing auxiliary valve controlled by the disk, for cutting off the supply of air from the supply pipe to the disk chamber, so that there will be no leakage of air from the casing around the valve-disk when the sanding mechanism is not in operation.
  • the invention also exemplifies an auxiliary valve which relieves the valve-disk of unilateral air-pressure, for reducing drag on the valve-disk and easing its operation.
  • a casing for supplying compressed air to the casing, the casing being provided with a seat and ports for air to the nozzle and to the clean-out duct in the trap, a rotatable disk having a face engaging said seat and provided with a port for selectively controlling air to said ducts, an auxiliar valve in the casing for cutting off the supply of air from the supply means to the disk, and cam means on and projecting transversely from the other face of the disk, including members for successively opening and closing the auxiliary valve during rotation of the disk to successively control air to the nozzle and the clean-out duct in the trap.
  • a casing for supplying compressed air in the casing, the casing being provided with a seat and ports for air to the nozzle and to the clean-out duct in the trap, a rotatable disk having a face engaging said seat and provided with a port for selectively controlling air to said ducts, an auxiliary valve in the casing for cutting oil the supply of air from the supply means to the disk, cam means integral with and projecting transversely from the other face of the disk, and including members for successively opening and closing the auxiliary valve during rotation of the disk to successively control air to the nozzle and the clean-out duct in the trap, and a lever shiftable by said members transversely to the disk.
  • a casing for supplying compressed air to the casing, a rotatable valve disk in the casing, said disk and casing being provided with means for selectively controlling air to the nozzle and the clean-out duct, an auxiliary valve in the casing for cutting oil the supply of air from the supply means to the disk, cam means on and rotatable with the disk, and a lever movably supported in the casing for movement transversely of the disk by said cam means, for opening the auxiliary valve to deliver air to the disk when it is rotated to deliver air to the nozzle or to the clean-out duct in the trap.
  • controllin mechanism for a, sand-trap provided with an air nozzle for discharging sand from the trap for application to a rail and a duct for a clean-out blast of the sand
  • a casing In controlling mechanism for a sand-trap provided With an air nozzle for discharging sand from the trap for application to a rail and a duct for a clean-out blast of the sand, the combination of a casing, means for supplying compressed air to the casing, a rotatable valve disk in the casing, said disk and easing being provided with means for selectively controlling air to the nozzle and the clean-out duct, an auxiliary valve in the easing for cutting off the supply of air from the supply means to the disk, cam means on and rotatable with the disk, the casing being provided with a groove, and a lever confined in the groove for movement transversely of the disk and shiftable by said cam means for delivering air to the disk when it is rotated to deliver air to the nozzle or the clean-out duct in the trap, and a spring for urging the lever against the disk and into engagement with the cam means.

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  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Mechanically-Actuated Valves (AREA)

Description

A ril 11, 1950 F. E. SAARI ET AL 2,503,417
CONTROLLING MECHANISM FOR SAND TRAPS Filed June 26, 1946 5 J f I Z] 46 g 2 5E 2 39 35 5206772 07 RAM/A E 677/78/ G/PW V. M 0 m Patented Apr. 11, 1950 UNITED STATES PATENT CIFFICE CONTROLLING MECHANISM FOR SAND TRAPS Frank E. Saari, Chicago, and Grant V. W. Roth, Evanston, Ill.
Application June 26, 1946, Serial No. 679,449
Claims.
discharge of sand for delivering it to the rails.
In this mechanism, one face of the rotatable disk fitted against a seat in the casing which was provided with conduits communicatively connected to the sand traps respectively. In practice, it has been found that leakage is sometimes caused by imperfectly fitting casin sections or engaging faces of the disk and its seat, or particles becoming lodged between said faces, or from other causes, so that when the disk was set to cut off the supply of compressed air to the sand trap, a considerable volume of compressed air was wasted.
The main object of the invention is to provide valve-mechanism of this type which include an auxiliary self-closing valve, controlled by the rotative movements of the valve-disk, for automatically cutting off the supply of compressed air to the valve-disk chamber in the casing, and thereby practically eliminating unilateral pressure and reducing drag on the valve-disk for ease of its operation, and also preventing leakage of air from the casing while the valve-disk is set to cut off the delivery of air to the trap, in the event that the casing sections, or the engaging faces of the l,
valve-disk and its seat in the casing, are imperfectly or defectively fitted, or particles become lodged between said faces.
Another object of the invention is to provide a valve of this type which is simple in construction and can be economically produced.
Other objects of the invention will appear from the detailed description.
The invention consists of the several novel features hereinafter set forth and more particularly defined by claims at the conclusion hereof.
In the drawings:
Figure 1 is a side elevation of a valve embodying the invention.
Figure 2 is a section taken on line 2-4 of ure 1.
Figure 3 is a perspective of the rotatable valvedisk.
Figure 4 is a section taken on line 4-4 of Figure'2.
Figure 5 is a section taken on line 5--5.
Figure 6 is a sectionillustrating theauxlliary valve in its open position, to admit the passage of compressed air to the disk valve.
The invention is exemplified in valve-mechanism which comprises a casing'formedof outlet and inlet sections Illand II, which are secured together by screws-I2. A pipe I3 leading from a source of compressed air supply, is connected to the section II of the casing. Pipes and I5 are connected to'receive air from separate conduits in the casing-section III, and are connected respectively to the ducts in a pairof sand traps, for delivering clean-out blasts to the sand traps, as well understood in the art. Pipes I6 and H are connected to receive air from separate conduits in casing-section I0, and are connected respectively to deliver air for discharging sand from a pairof traps, as well understoo'dinthe art. A chamber I8,-in the casing, is adapted to receive air from supply pipe I3, under control of the auxiliary valve hereinafter described. A valve-disk I9 is rotatable in the chamber I8, and has one of its faces fitting against the face 20 in casin section III, which forms a seat for said disk. Disk I9 is rotatable by a stud 2|, which is connected to the disk by a rib22. Stud H has afiixed thereto, a hand lever 23, which is provided with a spring pressed dog 24, adapted to engage a series of notches 26, formed in a segment on the casingsection III, for yieldably holding the lever in its different selective and predetermined positions. A port 21 extends through valve-disk I 9, and controls the flow of air. from chamber I8, to a pair of ducts 28, 29, in casing-section I0, which are communicatively connected to pipes I4 and I5 respectively, and to ducts 303I, which are communicatively connected to pipes I6 and I1 respectively. By rotation of the lever 23, disk I9 may be rotated toselectively supply air separately to the ducts 28, 29, 30 and 3|, for controlling the delivery of air through pipes I 4 and I5, to the clean-out ducts of the sand traps and pipes I6 and IT, to control the flow of air to the nozzles of sand traps for discharging sand onto the rails.
An auxiliary valve,.generally designated 33, is mounted in the inlet casing-section II, and controls the flow of air from a chamber 34, which is communicatively connected to the air supply pipe I3, through an opening 35, into the chamber I8. Valve 33 comprises a stem 36, whichis slidably mounted in a cap 31, a packing 38 secured on a head 39 by a screw 40,-and a washer III. :A spring 42 is adapted to normally close the exposed face of the packing disk 38, against a seat, which surrounds the opening 35. The auxiliary valve is controlled by an arcuate cam 46, which is integral with and projects from, one face of the valve-disk l9, and an arm or lever 43, which is fulcrumed at 44 on the center of disk I9, has a V-shaped corner 45, engaged by cam 46 and an extension or abutment 41, which is adapted to engage a part of valve 33, such as the screw 40, to force valve 33 away from its seat, against the force of spring 42. Lever 23 is confined against rotation with disk IS, in a recess 56 in casing-section ll. Lever 43 is urged toward disk l9 by a spring 48, which is confined in a socket in casing-section II, and exerts pressure against lever 43 for hOldiIlg disk [9 against its seat 20. Cam 46 comprises V-shaped members 49, which are adapted to shift valve 33 to its open position when the disk 19 is rotated in opposite directions, to bring port 21 into registry with ducts 28, 29 respectively, for delivering air for the clean-out blasts, and raised end-portions 50, which are adapted to shift lever 43, to open valve 33, when the disk I9 is rotated to bring port 21 into registry with the ducts 33, 3| respectively, for the delivery of sand from the sand traps. V-shaped depressions 51 in cam 46, are provided to permit valve 33 to close between the clean-out blasts and the discharge of the sand from the sand traps. When disk [9 is in position to cut oil flow of air through port 21, lever 43 engages a central V-shaped depression between members 49, and valve 33 will be closed. When valve 33 is in its open position, the pressure of spring 42, urges said valve toward its seat, and will also cause the V-shaped corner 45 of lever 43, to exert pressure on the inclined members of the V-shaped depressions in cam 46 for rotating the valve-disk into its cut-off positions.
The operation of the valve will be as follows: While lever 23 is in its neutral or central position, port 21 will be out of communication with any one of the ducts 28, 29, 30 and 3|, which lead to the pipes l4, I5, l6, 11, respectively. Valve 38 will then be closed against its seat 40, and spring 42 will hold lever 43 against disk I9, and the ilow of compressed air to chamber (9 will be cut oii. The pressure of spring 42 applied to lever 43, will be transmitted to disk [9, to hold it in engagement with the seat 20. As a result, at all times while disk I9 is in its neutral position, valve 33 will be closed, and no compressed air can leak around valve-disk 20. When lever 23 is shifted to rotate disk I9, and bring port 21 into registry with conduit 28 or 29, for delivering clean-out blasts to the traps, cam members 49 will shift lever 43 so its extension 41 will shift valve 33 against the force of spring 42, and cause air to pass from pipe l3 via chamber 34 and opening 35, into chamber 18, and through port 21, to the selected conduit 28 or 29. When lever 23 is shifted and disk [9 is rotated to bring port 21 into registry with either of the conduits 36 or 3|, one of the cam members 50 will shift lever 43 against the force of spring 48, and hold valve 33 open, while lever 23 remains set for discharging sand from the traps. When lever 23 is returned to its central position, from any of the positions in which it may have been set, disk 19 will be rotated to bring its port 21 out of registry with the conduits in the casing-section l0, and lever 43 will be retracted by spring 42, to release the auxiliary valve 33, and automatically cut oil communication between the air supply pipe 13 and the chamber l8. When the lever. 23is inadvertently left between its predetermined settings, according to the notches 26 in segment 25, for clean out blasts or discharging sand from the traps, respectively, the spring-pressure against lever 43 and the V-shaped corner 45 of said lever acting on the V-shaped depressions 5| in cam 46, will exert a rotative force on disk 19 to move it into the correct position for registry of its port 21 with one of the outlet conduits in the casing.
The invention exemplifies a controlling mechanism for a sand trap which comprises a rotatable valve-disk with a port therein, for controlling the delivery of sand to the sand traps, and an automatically closing auxiliary valve controlled by the disk, for cutting off the supply of air from the supply pipe to the disk chamber, so that there will be no leakage of air from the casing around the valve-disk when the sanding mechanism is not in operation. The invention also exemplifies an auxiliary valve which relieves the valve-disk of unilateral air-pressure, for reducing drag on the valve-disk and easing its operation.
ihe invention is not to be understood as limited to the details described, since these may be modified within the scope of the appended claims without departing from the spirit or scope of the invention.
Having thus described the invention, what we claim as new and desire to secure by Letters Patent is:
1. In controlling mechanism for a sand-trap provided with an air nozzle for discharging sand from the trap for application to a rail and a duct for a clean-out blast of the sand, the combination of a casing, means for supplying compressed air to the casing, the casing being provided with a seat and ports for air to the nozzle and to the clean-out duct in the trap, a rotatable disk having a face engaging said seat and provided with a port for selectively controlling air to said ducts, an auxiliar valve in the casing for cutting off the supply of air from the supply means to the disk, and cam means on and projecting transversely from the other face of the disk, including members for successively opening and closing the auxiliary valve during rotation of the disk to successively control air to the nozzle and the clean-out duct in the trap.
2. In controlling mechanism for a sand-trap provided with an air nozzle for discharging sand from the trap for application to a rail and a duct for a clean-out blast of the sand, the combination of a casing, means for supplying compressed air in the casing, the casing being provided with a seat and ports for air to the nozzle and to the clean-out duct in the trap, a rotatable disk having a face engaging said seat and provided with a port for selectively controlling air to said ducts, an auxiliary valve in the casing for cutting oil the supply of air from the supply means to the disk, cam means integral with and projecting transversely from the other face of the disk, and including members for successively opening and closing the auxiliary valve during rotation of the disk to successively control air to the nozzle and the clean-out duct in the trap, and a lever shiftable by said members transversely to the disk.
3. In controlling mechanism for a sand-trap provided with an air nozzle for discharging sand from the trap for application to a rail and a duct for a clean-out blast of the sand, the combination of a casing, means for supplying compressed air to the casing, a rotatable valve disk in the casing, said disk and casing being provided with means for selectively controlling air to the nozzle and the clean-out duct, an auxiliary valve in the casing for cutting oil the supply of air from the supply means to the disk, cam means on and rotatable with the disk, and a lever movably supported in the casing for movement transversely of the disk by said cam means, for opening the auxiliary valve to deliver air to the disk when it is rotated to deliver air to the nozzle or to the clean-out duct in the trap.
4. In controllin mechanism for a, sand-trap provided with an air nozzle for discharging sand from the trap for application to a rail and a duct for a clean-out blast of the sand, the combination of a casing, means for supplying compressed air to the casing, a rotatable valve disk in the casing, said disk and casing being provided with means for selectively controlling air to the nozzle and the clean-out duct, an auxiliary valve in the casing for cutting oiT the supply of air from the supply means to the disk, cam means on and rotatable with the disk, and a lever movably mounted in the casing for movement transversely of and fulcrumed on said disk, for opening the auxiliary valve to deliver air to the disk when it is rotated to deliver air to the nozzle or the clean-out duct in the trap, and spring means for urging the lever in engagement with the cam means.
5. In controlling mechanism for a sand-trap provided With an air nozzle for discharging sand from the trap for application to a rail and a duct for a clean-out blast of the sand, the combination of a casing, means for supplying compressed air to the casing, a rotatable valve disk in the casing, said disk and easing being provided with means for selectively controlling air to the nozzle and the clean-out duct, an auxiliary valve in the easing for cutting off the supply of air from the supply means to the disk, cam means on and rotatable with the disk, the casing being provided with a groove, and a lever confined in the groove for movement transversely of the disk and shiftable by said cam means for delivering air to the disk when it is rotated to deliver air to the nozzle or the clean-out duct in the trap, and a spring for urging the lever against the disk and into engagement with the cam means.
FRANK E. SAARI. GRANT V. W. ROTH.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,022,613 Vissering Apr. 9, 1912 2,238,140 Turner Apr. 15, 1941 FOREIGN PATENTS Number Country Date 3,384 Great Britain Feb. 11. 1909
US679449A 1946-06-26 1946-06-26 Controlling mechanism for sand traps Expired - Lifetime US2503417A (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB190903384A (en) * 1909-02-11 1909-11-11 Harry Edward Gresham Improvements in Sanding Appliances for Railway and like Vehicles.
US1022613A (en) * 1909-06-17 1912-04-09 Harry Vissering And Company Alarm-valve.
US2238140A (en) * 1940-05-04 1941-04-15 Morris B Brewster Co Inc Track sanding equipment

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB190903384A (en) * 1909-02-11 1909-11-11 Harry Edward Gresham Improvements in Sanding Appliances for Railway and like Vehicles.
US1022613A (en) * 1909-06-17 1912-04-09 Harry Vissering And Company Alarm-valve.
US2238140A (en) * 1940-05-04 1941-04-15 Morris B Brewster Co Inc Track sanding equipment

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