US3877385A - Rolling stock accelerator - Google Patents

Rolling stock accelerator Download PDF

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Publication number
US3877385A
US3877385A US461137A US46113774A US3877385A US 3877385 A US3877385 A US 3877385A US 461137 A US461137 A US 461137A US 46113774 A US46113774 A US 46113774A US 3877385 A US3877385 A US 3877385A
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United States
Prior art keywords
hydraulic
valve
working fluid
fluid under
under pressure
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Expired - Lifetime
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US461137A
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English (en)
Inventor
Kenichi Murato
Katsutoshi Sema
Mitsuru Wakao
Yoshinori Kobayashi
Koichi Hara
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Japan National Railways
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Japan National Railways
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B61—RAILWAYS
    • B61J—SHIFTING OR SHUNTING OF RAIL VEHICLES
    • B61J3/00—Shunting or short-distance haulage devices; Similar devices for hauling trains on steep gradients or as starting aids; Car propelling devices therefor

Definitions

  • ABSTRACT A rolling stock accelerator is disclosed which will start a railway car or similar vehicle moving from a standing start, and/or accelerate an already moving car at low speed.
  • a number of screw drums having helical fins mounted thereon are disposed axially in parallel with the rails of the track, with a mechanism for controlling their operation, all mounted upon a base.
  • each of the screw drums is rotated axially, causing the helical fins to engage the flanges of the car wheels, thereby moving the car forwad or accelerating it by means of the rising surface of the rotating fin impelling the wheel forward.
  • the present invention relates to an hydraulic rolling stock accelerator for starting and/or accelerating railway rolling stock or similar vehicles at low speeds. (Although there are many types of rolling stock. the word car is used herein to represent any and all such types.)
  • the plunger of an hydraulic cylinder disposed adjacent to a rail of a railway track is so arranged as to engage a wheel of a car approaching the accelerator. Therefore. a chamber defined by the cylinder and the plunger. which is caused to stroke by the wheel. changes its volume. This chamber is further divided by a sliding valve disposed within the cylinder into an upper and lower chamber. The sliding valve is adapted to be shifted at the ends of the extension and retraction strokes of the plunger in such a way that the upper chamber. that is the chamber below the plunger. may be connected with a low or high pressure hydraulic source through the lower chamber. Therefore. in the retraction or compression stroke in which the plunger in engagement with the wheel is retracted into the cylinder.
  • the upper chamber is connected with the low pressure hydraulic source so that the plunger may be retracted without resistance during almost all of the retraction or compres sion stroke.
  • the plunger may be retracted without decelerating force being applied to the wheel.
  • the sliding valve is mechanically shifted to that the upper chamber is connected with the high pressure hydraulic source so that when the wheel passes over the vertical passing through the pivot of the hydraulic cylinder.
  • the plunger is caused to be extended under the force of the working fluid under high pressure supplied from the high pressure source. thereby accelerating the wheel.
  • the sliding valve is shifted so that the upper chamber may be connected again with the low pressure hydraulic source in preparation for the next acceleration.
  • the conventional rolling stock accelerator of the type described has many defects.
  • the primary object of the present invention is therefore to provide a novel rolling stock accelerator capable of exerting stronger starting and accelerating forces to such railway cars and similar vehicles.
  • a number of screw drums having helical fins mounted on their outer surfaces are disposed axially in parallel along the rails of the railway track or the like and are driven by hydraulic motors which in turn are controlled by command units.
  • the helical fins of the screw drums are made to rotate axially and are thereby placed in driving contact with the flanges of the car wheels so that force may be transmitted to the wheels.
  • the car may be accelerated. or started even when it is stationary.
  • the angle of rotation of the screw drum in each acceleration step is automatically controlled so that continuous accelerating may be effected. Moreoever. the screw drums may be selectively shifted between their operative and inoperative positions. so that when they are inoperative. a car may freely pass over the accelerator.
  • FIG. I is the plan ofa rolling stock accelerator in accordance with the present invention.
  • FIG. 2 is the side elevation of an hydraulic starteraccelerator unit thereof.
  • FIG. 3 is the plan of FIG. 2.
  • FIG. 4 is the end elevation of FIG. 2.
  • FIG. 5 is the longitudinal vertical cross-section of the control valve assembly incorporated in the hydraulic unit shown in FIG. 2.
  • FIG. 6 is the longitudinal plan cross-section thereof.
  • FIG. 7 is a corss-sectional view taken along the line 7 -7 of FIG. 5.
  • FIG. 8 is a cross-sectional view taken along the line 8-8 of FIG. 5.
  • FIG. 9 is a cross-sectional view taken along the line 9-9 of FIG. 5.
  • FIG. 10 is a longitudinal cross section of a pulse generating valve.
  • FIG. 11 is an hydraulic circuit diagram of the described rolling stock accelerator to explain the mode of operation thereof.
  • the rolling stock accelerator generally indicated by FIG. 1 comprises a number of hydraulic units 22 disposed axially along a pair of rails 21; an hydraulic pressure source 23 for supplying the working fluid to the hydraulic units 22; an hydraulic unit control unit 24. and a number of command units 25 for giving the operational commands to the corresponding hydraulic units 22.
  • hydraulic-unit 22 includes a drive assembly 26. a control valve assembly 27. and a support assembly 28 which supports the driving and control valve assemblies 26 and 27 in parallel with rail 21 laid over foundation members 30, through a support 29 shown in FIG. 4.
  • the drive 26 generally comprises a screw drum 33 with a pair of helical fins 34 and an hydraulic motor 35.
  • One end of the shaft of screw drum 33 is rotatably supported by arm 31 and the other end by a gear box 32 coupled to hydraulic motor 35.
  • the pair of helical fins 34 mounted upon the screw drum 33 are angularly spaced apart from each other by 180 degrees and have a half-pitch.
  • the rotation of hydraulic motor 35 is transmitted through gear box 32 to screw drum 33 so that the rotating. rising edges of helical fins 34 are placed in driving contact with flanges 36 of the car wheels on rail 21 so as to start or accelerate the car as will be described in greater detail below.
  • control valve assembly 27 is interposed between arm 31 and gear box 32 in parallel with driving assembly 26. As shown in FIGS. and 6.
  • control valve assembly 27 includes an initial operation valve 37 adapted to give the start signal to hydraulic motor 35. and a rotary valve 38 coupled to screw drum 33 so as to interrupt the flow of the working fluid to hydraulic motor 35. thereby controlling the angle of rotation of screw drum 33.
  • a spool 40 is normally held in the position shown in FIGS. 5 and 6 under the force of a spring 39 to interrupt the flow of the working fluid supplied through an intake port 41 and a passage 42. But spool 40 is caused to be stroked to the left-hand direction against the spring 39 only when the pilot fluid flows into a pilot chamber 45 from a pilot port 43 through a passage 44.
  • the working fluid is supplied to hydraulic motor 35 from support port 41, passage 42. an annular grove 46, another annular groove 47, a passage 48 and a motor port 49.
  • the working fluid is returned from hydraulic motor 35 to a return line through another motor port 50. a passage 51. annular grooves 52 and 53, a passage 54 and a discharge port 55.
  • hydraulic motor 35 is rotated in a clockwise direction.
  • the rotary valve 38 comprises a stationary sleeve 56 and a sliding rotor 57 fitted into sleeve 56 and coupled through a rotary member 58 and gear box 32 to screw drum 33 and hydraulic motor 35.
  • the gear ratio of the gear box 32 is so selected that the rotor 57 in rotary valve 38 may be rotated at a speed one-half the rotary speed of hydraulic motor 35.
  • rotor 57 of rotary valve 38 is shown as being rotated through 45 degrees in FIGS. 5 and 6, but when hydraulic motor 35 is deenergized. ports 59 and 60 of rotor 57 are disconnected from ports 61 and 62 of sleeve 56 as shown in FIGS. 7. 8. and 9.
  • the ports 59 and 60 of the rotor 57 are connected with motor ports 49 and 50. respectively. through lateral ports 63 and 64. chambers 65 and 66, ports 67 and 68, annular grooves 69 and 70, ports 71 and 72 of the sleeve 56. annular chambers 73 and 74, and passages 48 and 51. respectively. Ports 61 and 62 of sleeve 56 are connected with passages 75 and 76, respectively.
  • hydraulic motor 35 in a clockwise direction may be continued. More particularly, rotation is continued until rotor 57 in rotary valve 38 is rotated in the direction indicated by the arrow through 90 so that communication between ports 59 and 60 on the one hand. and ports 61 and 62 of sleeve 56 on the other hand. is interrupted.
  • screw drum 33 is rotated through 180 degrees in a clockwise direction.
  • Hydraulic motor 35 is caused to rotate in a clockwise direction until rotor 57 rotates through 90. but when it rotates in excess of 90. ports 59 and 62 are connected and ports 60 and 61 are connected so that the flow of working fluid in hydraulic motor 35 is reversed.
  • hydraulic motor 35 is reversed and reverses rotor 57. In other words. when ports 59 and 60 of rotor 57 are closed by sleeve 56. rotary valve 38 reaches the stable or dead point.
  • passages 75 and 76 are alternately connected with the pressure and return lines in response to the signal of a detector which is set to detect the timing when the pilot fluid flows into pilot port 43. Therefore. whenever hydraulic motor 35 is rotated in a clockwise direction. as spool 40 in initial control valve 37 is shifted by the pilot fluid flow. the working fluid under pressure is always forced to flow through rotary valve 38 from motor port 49 to hydraulic motor 35. As a result. rotary valve 37 is caused to rotate through 90 in each step by hydraulic motor 35 so that the screw drum 33 is caused to rotate intermittently through 180 in each step in a clockwise direction.
  • a selection valve 77 and a directional control valve 78 are used as shown in FIGS. 5 and 6.
  • a spool 79 in selection valve 77 is normally pressed against a cam 81 formed at the end surface of rotor 57 of rotary valve 38 under the force of a spring 80, in such a way that spool 79 may be shifted as rotor 57 rotates through 90. As a result.
  • pilot fluid flowing from pilot port 43 into passage 44 is alternately forced to flow from an annular groove 82 through an annular groove 83 and a passage 85 into a left pilot chamber 87 in directional control valve 78 and through an annular groove 84 and a passage 86 into a right pilot chamber 88 of directional control valve 78.
  • pilot chambers 87 and 88 of directional control valve 78 are alternately connected to discharge port 55 through passages 85 and 86 and annular grooves 83 and 84, respectively. the annular groove 89. and the passages 90 and 76. respectively.
  • passage 75 in directional control valve 78 is shifted each time when rotor 57 in rotary valve 38 is rotated through 90 degrees so that passage 75 is connected with supply port 41 through annular grooves 92 and 94, and passage 42, while passage 76 is connected with discharge port 55 through annular grooves 93 and 95. and passage 76 or vice versa.
  • passages 75 and 76 are alternately connected with the pressure and reutrn lines.
  • support assembly 28 comprises two pairs of rocking arms 97 to connect arm 31 and gear box 32 to brackets 96. respectively. which in turn are attached to foundation members 30, and two hydraulic cylinders 98 interposed between foundation members 30 and arm 31 and gear box 32. respectively.
  • hydraulic cylinders 98 When the hydraulic cylinders 98 are extended. the edges of the helical fins 34 mounted upon screw drum 33 of driving assembly 26 are moved to the operative position to engage flange 36 of the car wheel.
  • valve casing 100 which are slidably fitted into sleeve 101. and an operating arm 107 hinged respectively by pins 105 and 106 to the leading ends of operating rod 103 and an arm 104 extending from valve casing 100.
  • Sleeve 101 defines a cylinder chamber 108 between sleeve 101 and valve casing 100 at one end thereof.
  • a coiled spring 111 is loaded between valve casing 100 and a spring seat 110 mounted on an extension rod 109 extending outwardly from the end of the valve casing so that pulse-generating valve 99 may normally be in the retracted position shown in FIG. under the force of coiled spring 111.
  • a roller 112 attached to the leading end of operating arm 107 is retracted from the upper surface level of rail 21. But when the working fluid under pressure is forced into cylinder 108 through a port 113 and a passage 114 formed through valve casing 100. spool 102 and hence operating rod 103 are pushed outwardly so that roller 112 at the upper end of operating arm 107 is extended above the surface of rail 21.
  • Spool 102 is normally held in the position shown in FIG. vl0 under the force of a coiled spring 115 loaded between sleeve 101 and the extension rod 109 so that a delivery port 116 communicates through. as follows: a passage 117; an annular groove 118; a chamber 119; an annular groove 120 of spool 102; a chamber 121: an annular groove 112'. and a passage 123. to a discharge port 124. But when roller 112 at the end of operating arm 107 is pushed down by the wheel.
  • operating arm 107 pushes operating rod 103 and spool 102 inward so that delivery port 116 is connected as follows: through passage 117; annular groove 118; chamber 119; annular groove 125 of spool 102;-chamber 126; annular groove 127; and a passage 128. to a supply port 129.
  • the working fluid under pressure is forced into pilot chamber 130. between one end of spool 102 and sleeve 101. from pilot port 131 through a passage 132 and an annular groove 133.
  • spool 102 is forced inward regardless of the position of operating arm 107 so that delivery port 116 is connected with supply port 129.
  • an hydraulic pressure source generally indicated by 23 comprises, as follows:
  • a high pressure pump 134 a low pressure pump 135;
  • relief valves 136 and 137 for controlling the maximum discharge pressures of high and low pressure pumps 134 and 135, respectively; an accumulator 138 with a pilot check valve 139 for storing the working fluid under pressure supplied from high pressure pump 134: the first, second and third sequence valves I40. 141 and 142 inserted in the line connected to low pressure pump 135; accumulators 143, 144, 145. and 146; check valves 147,- 148, 149, 150. 151 and 152. and a pressure pilot valve 153.
  • the control unit generally indicated by 24 comprises solenoid-controlled valves 154 and 155 for shifting hydraulic units 22 between their operative and inoperative positions.
  • Hydraulic units 22, hydraulic pressures source 23. control unit 24 and command unit 25 are hydraulically interconnected as shown in FIG. 11.
  • hydraulic motor 35 is rotated in a clockwise direction under the force of the working fluid under higher pressure so that the tins of the screw drum are forced against the wheel flange and cause the wheel to turn.
  • the car may be started from a stationary position.
  • Suitable means for detecting car speed such as a tachometer (not shown) is mounted on screw drum 33, hydraulic motor 35, or rotor 57 of rotary valve 38 in such a way that when the speed of the started and/or accelerated car reaches a predetermined velocity.
  • the solenoid-controlled valves 154 and 155 are actuated in response to a signal from the tachometer so as to return hydraulic units 22 and pulse-generating valves 99 to their inoperative positions.
  • car speed may be controlled in a very simple manner by this present invention.
  • the present invention may be used not only for starting and accelerating rolling stock but also for pushing cars along up-graded tracks. Furthermore. when the rolling stock accelerator is retracted to its inoperative position, rolling stock may freely pass over it. Thus the rolling stock accelerator in this present invention may find a wide variety of applications.
  • a Rolling Stock Accelerator comprising the following:
  • A. A number of hydraulic units disposed along the rails of a railway track or the like.
  • B. An hydraulic pressure source for supplying working fluid under pressure to these hydraulic units.
  • C. A command unit for controlling the operation of a number of hydraulic units. each of which includes the following:
  • a drive assembly comprising an hydraulic motor and a screw drum having helical fins mounted thereon to make driving contact with the flange of a car wheel. said screw drum being driven by the hydraulic motor.
  • a control valve assembly including an initial operation valve adapted to give the start signal to the hydraulic motor in response to a command signal from the command unit. and a rotary drum coupled to the screw drum so as to interrupt the flow of working fluid under pressure to the hydraulic motor. thereby controlling the angle of rotation of said screw drum.
  • a support assembly including a number of hydraulic cylinders interposed between the base and the drive assembly and command unit so as to selectively shift them from their inoperative positions to their operative positions or vice versa.
  • a Rolling Stock Accelerator comprising the following:
  • A. A number of hydraulic units disposed along the rails ot a railway track or the like.
  • B. An hydraulic pressure source for supplying working fluid under pressure to these hydraulic units.
  • C. A pulse-generating valve adapted to detect a car entering the rolling stock accelerator so as to give a pulse signal. and a number of hydraulic units each of which includes the following:
  • a drive assembly comprising an hydraulic motor and as screw drum having helical fins mounted thereon to make driving contact with the flange of a car wheel. said screw drum being driven by the hydraulic motor.
  • a control valve assembly including an initial operation valve adapted to give the start signal to the hydraulic motor in response to the pulse signal derived from the pulse-generating valve: a rotary valve coupled to the screw drum in such a way that the flow of working fluid under pressure to the hydraulic motor may be interrupted at angularly symmetrical dead points; a selection valve adapted to be shifted synchronously with the actuation or shift of the rotary valve. and a directional control valve coupled to the selection valve so as to control the direction of the working fluid under pressure flowing to the rotary valve.
  • a support assembly comprising a number of hydraulic cylinders interposed between the base and the drive assembly and the pulse-generating valve so as to selectively shift them from their inoperative positions to their operative positions or vice versa.
  • a Rolling Stock Accelerator comprising the following:
  • a pulse-generating valve adapted to detect a car entering the rolling stock accelerator so as to give a pulse signal. and a number of hydraulic units each of which includes the following:
  • a drive assembly comprising an hydraulic motor and a screw drum having helical fins mounted thereon to make driving contact with the flange of a car wheel. said screw drum being driven by the hydraulic motor.
  • a control valve assembly including an initial operation valve adapted to give the start signal to the hydraulic motor in response to the pulse signal derived from the pulse-generating valve: a rotary valve coupled to the screw drum in such a way that the flow of working fluid under pressure to the hydraulic motor may be interrupted at angularly symmetrical dead points, thereby controlling the angle of rotation of said screw drum; a selection valve adapted to be shifted synchronously with the actuation or shift of the rotary valve. and a directional control valve coupled to the selection valve so as to control the direction of the working fluid under pressure flowing into the rotary valve.
  • a support assembly comprising a number of hydraulic cylinders interposed between the base and the drive assembly and the pulse-generating valve so as to selectively shift them from their inoperative positions to their operative positions or vice versa.
  • the said hydraulic pressure source comprising:
  • High and low pressure hydraulic sources for supplying working fluid under pressure to accelerate a car.
  • a first-sequence valve adapted to be opened after the rotary valves have been reset so as to cause working fluid under pressure supplied from the low pressure source to flow into the hydraulic cylinders in the support assemblies ofthe hydraulic units. thereby shifting the drive assemblies of the hydraulic units and pulse-generating valves to their operative positions.
  • a second-sequence valve adapted to be opened after the drive assemblies and the pulsegenerating valves have been shifted to their operative positions so as to direct working fluid under pressure supplied from the low pressure source to the pulse-generating valves. thereby shifting the same so as to cause each of the hydraulic units to idle once.
  • a third-sequence valve adapted to be opened after each of the hydraulic units has made one idle operations so as to direct working fluid under pressure supplied from said low pressure source to a pilot check valve and to connect the rotary valves of the control valve assemblies of the hydraulic units with the high-pressure hydraulic source.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Control Of Velocity Or Acceleration (AREA)
  • Vehicle Body Suspensions (AREA)
US461137A 1973-04-17 1974-04-15 Rolling stock accelerator Expired - Lifetime US3877385A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP48042727A JPS5225607B2 (enrdf_load_stackoverflow) 1973-04-17 1973-04-17

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US3877385A true US3877385A (en) 1975-04-15

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US461137A Expired - Lifetime US3877385A (en) 1973-04-17 1974-04-15 Rolling stock accelerator

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US (1) US3877385A (enrdf_load_stackoverflow)
JP (1) JPS5225607B2 (enrdf_load_stackoverflow)
CA (1) CA993763A (enrdf_load_stackoverflow)
DE (1) DE2418531C3 (enrdf_load_stackoverflow)
FR (1) FR2226312B1 (enrdf_load_stackoverflow)
GB (1) GB1465705A (enrdf_load_stackoverflow)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2338657C1 (ru) * 2007-01-09 2008-11-20 Александр Анатольевич Демьянов Тормозная система для сортировочных горок

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5299506A (en) * 1976-02-14 1977-08-20 Japanese National Railways<Jnr> Decelerator for vehicle
JPS5343302A (en) * 1976-09-29 1978-04-19 Japanese National Railways<Jnr> Vehicle accelerating apparatus
JPS56166967U (enrdf_load_stackoverflow) * 1981-03-05 1981-12-10
DE4429321C2 (de) * 1994-08-18 1997-10-09 Heinz Thate Landgestützte Hochgeschwindigkeits-Großraumtransportfähre

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1298285A (en) * 1918-09-11 1919-03-25 Philadelphia Textile Mach Co Drying apparatus.
US2624440A (en) * 1951-06-09 1953-01-06 Armstrong Cork Co Device for controlling movement of a member on a conveyer
US3352250A (en) * 1963-03-22 1967-11-14 Battelle Development Corp Transport apparatus
US3605631A (en) * 1968-12-05 1971-09-20 Mattel Inc Moving apparatus for a toy vehicle
US3793964A (en) * 1972-03-20 1974-02-26 Mcdowell Wellman Eng Co Railroad car spotting and wheel locking apparatus

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE919536C (de) * 1953-01-25 1954-10-25 Friedrich Raab Dr Ing Einrichtung zur Minderung oder Vernichtung der Bewegungsenergie von Fahrzeugen, insbesondere von Eisenbahnwagen
US3128721A (en) * 1961-06-09 1964-04-14 Westinghouse Air Brake Co Weight proportional vehicle speed controlling apparatus

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1298285A (en) * 1918-09-11 1919-03-25 Philadelphia Textile Mach Co Drying apparatus.
US2624440A (en) * 1951-06-09 1953-01-06 Armstrong Cork Co Device for controlling movement of a member on a conveyer
US3352250A (en) * 1963-03-22 1967-11-14 Battelle Development Corp Transport apparatus
US3605631A (en) * 1968-12-05 1971-09-20 Mattel Inc Moving apparatus for a toy vehicle
US3793964A (en) * 1972-03-20 1974-02-26 Mcdowell Wellman Eng Co Railroad car spotting and wheel locking apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2338657C1 (ru) * 2007-01-09 2008-11-20 Александр Анатольевич Демьянов Тормозная система для сортировочных горок

Also Published As

Publication number Publication date
FR2226312B1 (enrdf_load_stackoverflow) 1980-06-27
DE2418531C3 (de) 1981-12-17
DE2418531B2 (de) 1981-04-23
FR2226312A1 (enrdf_load_stackoverflow) 1974-11-15
JPS49128406A (enrdf_load_stackoverflow) 1974-12-09
JPS5225607B2 (enrdf_load_stackoverflow) 1977-07-08
DE2418531A1 (de) 1974-11-14
GB1465705A (en) 1977-03-02
CA993763A (en) 1976-07-27

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