EP0019352B1 - Système de commande de treuils - Google Patents

Système de commande de treuils Download PDF

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Publication number
EP0019352B1
EP0019352B1 EP19800301041 EP80301041A EP0019352B1 EP 0019352 B1 EP0019352 B1 EP 0019352B1 EP 19800301041 EP19800301041 EP 19800301041 EP 80301041 A EP80301041 A EP 80301041A EP 0019352 B1 EP0019352 B1 EP 0019352B1
Authority
EP
European Patent Office
Prior art keywords
brake
fluid
piston
accumulator
port
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19800301041
Other languages
German (de)
English (en)
Other versions
EP0019352A3 (en
EP0019352A2 (fr
Inventor
Kenneth F. Golan
James E. Winzeler
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Caterpillar Inc
Original Assignee
Caterpillar Tractor Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Caterpillar Tractor Co filed Critical Caterpillar Tractor Co
Publication of EP0019352A2 publication Critical patent/EP0019352A2/fr
Publication of EP0019352A3 publication Critical patent/EP0019352A3/en
Application granted granted Critical
Publication of EP0019352B1 publication Critical patent/EP0019352B1/fr
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
    • B66D5/00—Braking or detent devices characterised by application to lifting or hoisting gear, e.g. for controlling the lowering of loads
    • B66D5/02—Crane, lift hoist, or winch brakes operating on drums, barrels, or ropes
    • B66D5/24—Operating devices
    • B66D5/26—Operating devices pneumatic or hydraulic

Definitions

  • This invention relates to control systems for hydraulically operated draw works having winches, or the like, and which may have hydromechanical boom or hook type draw works transmission controls.
  • Winches or as more generally known, draw works, are used in a large variety of operations and, as a consequence, there are draw works constructions available with widely varying degrees of sophisticated control and drive equipment.
  • Some of the more sophisticated draw works constructions are hydraulically operated and include a hydraulic motor for driving a draw works drum.
  • a hydraulically disengaged brake which brakes the drum to prevent unduly rapid lowering of a load to be hoisted.
  • a multiple-speed, hydraulically controlled transmission may interconnect the drum and the drive motor therefor.
  • the first is the so-called “drop and catch” lowering wherein the brake is fully disengaged and the load is allowed to fall at its maximum rate.
  • the brake is once again engaged and further lowering is arrested.
  • the second type of lowering is the so-called “controlled” lowering in which the brake is only partially disengaged thereby allowing a load to be lowered at some controlled rate less than the maximum.
  • DE-A-1431991 discloses the use of an accumulator in a control system for a winch brake which is hydraulically disengaged, the accumulator modulating application of the brake by means of a piston within the accumulator acted upon by a spring and acting on the hydraulic fluid in connection with the brake.
  • a control system for a spring-applied hydraulically-disengaged brake having a source of fluid under pressure; a control valve having a fluid inlet connected to the source of fluid and a fluid outlet; and an accumulator is characterized in that the accumulator is connected between the fluid outlet of the control valve and the brake, the accumulator including a body having a bore, an inlet port in the body connected to the control valve, and outlet port in the body connected to the brake a piston slidably disposed in the bore, an accumulator chamber one one side of the piston in fluid communication with the outlet port, a spring pocket located on the other side of the piston; a spring positioned within the spring pocket and biasing the piston towards a predetermined position within the bore, means for connecting the inlet port with the spring pocket, and a metering orifice connecting the spring pocket with the accumulator chamber to permit, in use a continuous but limited rate of fluid flow between the outlet port and the inlet port.
  • FIG. 1 One example of a control system for a hydraulically operated draw works or the like including a hydraulically disengaged brake, a multi-speed, hydraulically controlled transmission and a drum to be driven or braked is illustrated in the drawings and, with reference to Figure 1, is seen to include a multi-speed, hydraulically controlled transmission including a high speed section indicated schematically at 10 and a low speed section schematically indicated at 12.
  • the transmission including the components 10 and 12 is of the type that when fluid under pressure is directed to the high speed section 10, the output speed of the transmission will be in high gear, and when fluid under pressure is directed to the low speed section 12, the output speed of the transmission will be in the low range.
  • the draw works assemblage includes a spring-engaged, hydraulically disengaged brake which may be of conventional construction and which is illustrated schematically at 14.
  • the system also includes a metering pump 16 which will be suitably coupled to the draw works drum (not shown) through a one-way clutch (not shown) so as to be driven thereby when the load is lowered at a speed proportional to the rate of rotation of the draw works drum.
  • the purpose of the metering pump 16 is to act as a governor and limit the rotational velocity of the drum.
  • a hydraulic pump 20 typically driven by the prime mover of the vehicle.
  • the pump 20 receives oil from a reservoir 22 and directs the same, under pressure, to a junction 24.
  • One side of the junction 24 extends to a priority valve 26 which, in turn, permits the flow of fluid to the vehicle components 18.
  • the other side of the junction 24 extends to the control system of the present invention.
  • the priority valve 26 is of conventional construction and is operative to ensure delivery of fluid to the control system of the present invention at a pressure equal to or exceeding a predetermined minimum pressure. Frequently, hydraulic fluid flow requirements of the vehicle components 18 will cause the pressure to drop to a relatively low value which is insufficient to maintain engagement of the components of the transmission. The priority valve 26 prevents such from occurring.
  • the control system includes a control valve, generally designated 28, which comprises two valves in a common housing.
  • Manual actuators, generally designated 30, are provided for the valve 28 in, for example, an operator area.
  • the manual actuators 30 include, for example, a handle 32 which may be grasped by the operator to perform a variety of functions to be described.
  • a console within the operator area is provided with a slot 34 in which the handle 32 may be moved.
  • a first mechanical link shown schematically at 36, is attached to the handle 32 and extends to the control valve 28 to convey thereto mechanical motion of the handle 32 directing the secltion of a particular transmission output speed.
  • a similar linkage shown schematically at 38, extends to a brake control section of the valve 28 to convey mechanical movement of the handle 32 to the valve 28 to direct the flow of hydraulic fluid under pressure to the brake 14 to control its degree of disengagement.
  • a third linkage extends to a motor speed and direction control system (not shown) which is operative to control the speed of the hydraulic drive motor for the draw works as well as its directional output.
  • the linkages 36, 38 and 40 may be conventional in nature and, for example, in the form of control cables or linkages. It is only necessary that the linkage 36 be responsive to movement of the handle 32 in the right-left direction, as viewed in Fig. 1, and nonresponsive to other direction of movement thereof.
  • the linkages 38 and 40 are similar, but are responsive only to up-down movements of the handle 32, as viewed in Fig. 1, and nonresponsive to left-right movement.
  • the slot 34 defines a shift pattern for the handle 32. It includes a horizontally elongate slot 42. When, as viewed in Fig. 1, the handle 32 is disposed in the left-hand end of the slot 42, the control valve 28 will direct the transmission to select its high speed output. When the handle 32 is in the right-hand extremity of the slot 42, it will direct the control valve 28 to select the low speed range of the transmission.
  • each end of the slot 42 there are provided downwardly extending slots 44 and 46.
  • the linkage 40 will direct the motor speed and direction control system to drive the drum of the draw works to elevate the load.
  • the degree of depression of the handle 32 in either of the slots 44 or 46 will control the speed of the drive motor for the winch.
  • an upwardly extending slot 48 intermediate the ends of the slot 42.
  • a direction by the valve 28 to the transmission will cause the latter to assume a neutral condition.
  • the brake 14 will be allowed to progressively disengage as the handle 32 moves further up the slot.
  • the linkage 40 may be directed, after the backlash has been taken up, to drive the drum motor in a direction to lower the load at a particular speed, but only if the load is not of sufficient magnitude for gravity to overcome the friction of the draw works assemblage.
  • a short, downwardly extending slot 50 intersects the slot 42 intermediate its ends. WHen the handle 32 is directed downwardly into the slot 50, there will be a direction to the motor speed and direction control system to energize the drive motor for the draw works.
  • hydraulic fluid under pressure is directed along a line 52 to the transmission control side of the valve 28 in a manner to be described in greater detail hereinafter. It is also directed to a check valve system 54.
  • the check valve system 54 includes a first check valve 56 which precludes backflow from any downstream component to the junction 24. Just downstream of the check valve 56 there is located a junction 58. Connected to the junction 58 is a check valve 60 which extends to the metering pump 16. The check valve 60 precludes discharge of an accumulator 62 except through the valve 28.
  • the valve 28 includes a housing 100 formed of a center housing 102, a right end housing 104 and a left end housing 106.
  • the left end housing 106 receives, in a conventional fashion, cable ends 108 and 110 of the linkages 36 and 38, respectively.
  • the center housing 100 includes a transmission control bore 112 and a brake control bore 114.
  • the housing 104 includes cavities 116 which are aligned with the bores 112 and 114 and house bi-directional spring centering assemblies 118 which are operative to center respective ones of a transmission control spool 120 in the bore 112 and a brake control spool 122 in the bore 114 to the positions illustrated in Figure 2 regardless of whether the spools 120 and 122 have been shifted to the right or to the left.
  • the spools 120 and 122 have leftward extensions which extend into the housing 105 for connection to the cable ends 108 and 110 whereby the spools 120 and 122 may be shifted to the right or to the left in in their bores by manipulation of the handle 32, as mentioned previously.
  • the transmission control spool 120 does not need to be further described for the purposes of the present invention.
  • the brake control bore 114 includes a cavity 150 which is connected to junction 58 for receipt of fluid under pressure.
  • an outlet port 152 which is adapted to be connected to both a brake accumulator 174 and to the metering pump 16, as shown in Fig. 4.
  • the outlet port 152 is disposed between the cavity 150 and the outlet port 132 which extends to the reservoir 22.
  • the spool 122 includes a land 158 having a relatively long axial length which is normally operative to preclude the flow of fluid from the cavity 150 to the outlet port 152 while allowing flow of fluid from the outlet port 152 to drain through the drain port 132 or to interrupt fluid communication between the drain port 132 and the outlet port 152 and allow fluid to flow from the cavity 150 to the outlet port 152 under circumstances to be described in greater detail hereinafter.
  • the land 158 includes oppositely disposed, axially extending grooves 160, 162 and 164 in its periphery.
  • Each of the grooves 160, 162 and 164 opens to the inlet side of the land 158 and, as can be best seen in Fig. 2, the groove 160 has a relatively long axial length, the groove 162 has an intermediate axial length, while the groove 164 has a relatively short axial length.
  • the grooves 162 and 164 have relatively large cross sections, while the groove 160 has a relatively small cross section.
  • all three grooves have a progressively decreasing cross section from left to right (Fig. 2).
  • the grooves 160, 162 and 164 serve as metering grooves to assist in attaining such a degree of brake disengagement control. Specifically, the further the spool 122 is moved to the right, as viewed in Fig. 2, the greater the fluid flow from the cavity 150 to the outlet 152 through the grooves 160. The greater the fluid flow, the greater the degree of disengagement of the brake 14 which, it will be recalled, is of the hydraulically disengaged type.
  • a spring 166 has been included to provide positive feedback to the operator. As the leading edge of the groove 164 approaches the leftmost surface of cavity 168 which leads to port 152, the washer 167 contacts a shoulder 170 of the bore 114. Any further rightward movement of spool 122 compresses the spring 166 and provides for a positive operator feel when the maximum speed groove 164 has been entered.
  • fluid flowing from the port 152 will flow to a junction 172 and simultaneously to the metering pump 16 and a brake accumulator, generally shown at 174.
  • the brake is of the spring engaged-hydraulically disengaged type and therefore the brake 14 may be disengaged, with the load lowered, only by supplying brake 14 with hydraulic fluid from the port 152.
  • the greater the fluid pressure the greater the degree of disengagement and the greater the quantity of fluid required to cause progressive disengagement.
  • the brake 14 can only be supplied with hydraulic fluid through the brake accumulator 174.
  • Hydraulic fluid metered through the grooves 160, 162 and 164 is supplied to a brake accumulator port 176 in a housing 178 of the accumulator 174.
  • a bore 180 which contains a piston 182.
  • the piston 182 has a relatively thin wall 184 which is perforated by a number of passageways 186. As viewed in Fig. 4, the piston is urged to the left by springs 188 and 190.
  • the spring pocket 192 is ultimately connected to the brake 14 by a passageway 194, a check valve 196, an accumulator chamber 198 and an accumulator port 200.
  • a brake release piston 202 Located within the brake 14 is a brake release piston 202, a brake return spring 204 and a brake cylinder 206.
  • the brake 14 is otherwise conventional in construction and need not be further explained. It is sufficient to note that when the piston 202 is in the leftmost position, as viewed in Fig. 4, the brake 14 will be fully applied and as the piston 202 is forced an increasing distance to the right by pressurized fluid in the cylinder 206, the brake 14 will be increasingly released.
  • the piston return spring 204 creates a force opposing fluid pressure in the cylinder 206. Therefore, if fluid pressure in chamber 206 is in- adequate to overcome the force created by the spring 204, the piston 202 will be urged to the left and the brake 14 will be. applied.
  • the pressure of the hydraulic fluid supplied from the outlet port 152 to the accumulator port 176, and consequently the brake 14, may be varied by operator actuation of the brake spool 122.
  • brake release will be accomplished by one of two methods. If fluid supply pressure is high, the force on the piston 202 will be sufficient to completely overcome the force created by the spring 204. In this case, the brake piston 202 will be forced fully to the right and the brake 14 will be completely released. As a consequence of this large piston 202 movement, a large volume of hydraulic fluid will enter the brake cylinder 206.
  • a relatively low hydraulic fluid pressure will be insufficient to completely overcome the force created by the return spring 204 and the brake piston 202 will be forced only a short distance to the right. This piston movement will be insufficient to completely release the brake 14 but will cause slippage. In this situation, the volume of fluid entering the piston cylinder 206 will be relatively small.
  • piston surfaces 208 and 210 Located on the piston 182 are piston surfaces 208 and 210 upon which the fluid located in the accumulator chamber 198 will act.
  • piston surfaces 208 and 210 Located within a piston wall 212 is a metering orifice 214 which establishes fluid communication between the accumulator chamber 198 and the accumulator port 176 through the piston passageways 186.
  • the accumulator chamber 198 will no longer be in direct fluid communication with the port 176 and any remaining fluid in the accumulator chamber 198 and the brake cylinder 206 must flow through the metering orifice 214 and the piston passageways 186.
  • the metering orifice 214 will limit the flow of fluid from the piston cylinder 206 and thus cause gradual application of the brake 14.
  • the fluid Upon reaching the accumulator port 176, the fluid flows through the piston passages 186, the spring pocket 192, the passageway 194, the check valve 196 and finally through the accumulator port 200 to the brake cylinder 206.
  • the accumulator chamber 198 will become completely filled during this process.
  • the brake spool 122 When it is desired to stop descent of the load, the brake spool 122 is shifted to the neutral position as shown in Fig. 2. As indicated above, the outlet port 152 will then be in fluid communication with the drain port 132, and consequantly, the tank 22. The accumulator spring pocket 192 and the passageway 194 with thus be drained by the drain port 132. Fluid pressure in the accumulator chamber 198 and the piston cylinder 206 will then cause the check valve 196 to be completely seated.
  • the piston surface 208 will clear the edge 216 of the port 176 and the piston 182 will act as a relief valve.
  • the springs 188 and 190 will force the piston 182 to once again move towards the left, closing off accumulator port 176.
  • any further fluid flow from the accumulator chamber 198 and the brake cylinder 206 must be through the metering orifice 214.
  • the limited flow through the metering orifice 214 will cause the gradual relief of fluid pressure in the brake cylinder 206 and thus provide modulated brake application and gradual arrest of the load.
  • fluid flow from the cavity 150 to the outlet 152 will be through less than all of the grooves 160, 162 and 164. This will generate a fluid pressure in the brake cylinder 206 which will be less than that required to completely release the brake 14. However, fluid pressure in the cylinder 206 will be of a magnitude that will cause slippage and limited rotation of the brake 14. Since the brake piston 202 will move only a slight distance to the right, a relatively small volume of fluid will be contained in the brake cylinder 206.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Regulating Braking Force (AREA)
  • Braking Arrangements (AREA)

Claims (4)

1. Système de commande (28) pour un frein (14) à serrage par ressort et à desserrage hydraulique ayant une source de fluide sous pression (20); une valve de commande (114, 122) ayant une entrée de fluide (156) reliée à la source de fluide et une sortie de fluide (152); et un accumulateur (174), caractérisé en ce que l'accumulateur (174) est connecté entre la sortie de fluide (152) de la valve de commande et le frein (14), l'accumulateur comprenant un corps (178) ayant un alésage (180), un orifice d'entrée (176) dans le corps (178) relié à la valve de commande (114, 122), un orifice de sortie (200) dans le corps (178) relié au frein (14), un piston (182) disposé à glissement dans l'alésage (180), un chambre d'accumulateur (198) d'un côté du piston en communication de fluide avec l'orifice de sortie (200), un logement de ressort (192) situé de l'autre côté du piston; un ressort (188, 190) placé dans le logement de ressort (192) et sollicitant le piston vers une position prédéterminée dans l'alésage, un moyen (186, 216) pour relier l'orifice d'entrée (176) au logement de ressort (192), et un orifice de réglage (214) reliant le logement de ressort (192) à la chambre d'accumulateur (198) afin de permettre, pendant l'utilisation, une circulation de fluide à un continu mais limité entre l'orifice de sortie (200) et l'orifice d'entrée (176).
2. Système de commande selon la revendication 1 dans lequel le piston (182) a un intérieur creux et dans lequel l'orifice de réglage (214) est logé dans le piston, s'étendant de l'intérieur creux (184) du piston à la surface extérieure du piston.
3. Système de commande selon la revendication 2, dans lequel le moyen (186, 216) pour faire communiquer le premier orifice (176) avec le logement de ressort (192) comprend un canal (186) s'étendant de l'intérieur creux (184) du piston (182) à la surface extérieure.
4. Système de commande selon l'une quelconque des revendications 1 à 3, comprenant en outre une valve antiretour (196) disposée entre le logement de ressort (192) et la chambre d'accumulateur (198) afin de permettre une circulation sans restriction du fluide à travers la valve antiretour du logement de ressort (192) à l'accumulateur (198) et d'empêcher une circulation de fluide de la chambre d'accumulateur (198) au logement de ressort (192), abstraction faite de la circulation à travers l'orifice de réglage.
EP19800301041 1979-05-02 1980-04-02 Système de commande de treuils Expired EP0019352B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
PCT/US1979/000293 WO1980002446A1 (fr) 1979-05-02 1979-05-02 Commande de transmission d'une machine d'etirage
WOPCT/US79/00293 1979-05-02

Publications (3)

Publication Number Publication Date
EP0019352A2 EP0019352A2 (fr) 1980-11-26
EP0019352A3 EP0019352A3 (en) 1981-02-18
EP0019352B1 true EP0019352B1 (fr) 1984-07-11

Family

ID=22147578

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19800301041 Expired EP0019352B1 (fr) 1979-05-02 1980-04-02 Système de commande de treuils

Country Status (5)

Country Link
EP (1) EP0019352B1 (fr)
JP (1) JPH025680B2 (fr)
DE (1) DE3068492D1 (fr)
SU (1) SU1074400A3 (fr)
WO (1) WO1980002446A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3152968C2 (de) * 1981-09-11 1993-10-07 Caterpillar Inc Steuersystem mit selektiver Druckunterteilung

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR657612A (fr) * 1927-07-18 1929-05-24 Vickers Electrical Co Ltd Perfectionnements aux dispositifs de freinage des appareils ou dispositifs mobiles notamment des mécanismes des treuils d'enroulement, de traction, d'extraction, etc.
US2355749A (en) * 1943-05-31 1944-08-15 Polson Alexander David Brake for hoist machinery
DE1011132B (de) * 1954-11-12 1957-06-27 Siemens Ag Vereinigte Fahr- und Sicherheitsbremse fuer Foerdermaschinen
US2912286A (en) * 1957-03-29 1959-11-10 New York Air Brake Co Fluid pressure power brake system
US3170543A (en) * 1962-12-06 1965-02-23 Goodyear Tire & Rubber Delay valve
DE1431991A1 (de) * 1966-09-01 1969-07-10 Gutehoffnungshuette Sterkrade Bedienungsvorrichtung fuer den hydraulischen Bremsapparat einer Bergbau-Schachtfoerdermaschine od.dgl.
US3463278A (en) * 1967-11-02 1969-08-26 Caterpillar Tractor Co Transmission and brake for cable drum with modulating valve
CA883111A (en) * 1968-10-26 1971-10-12 Deh. Eastcott Peter Control of mine hoist braking
US4046162A (en) * 1976-05-14 1977-09-06 Deere & Company Modulation control valve for clutches
US4048799A (en) * 1976-11-17 1977-09-20 Caterpillar Tractor Co. Winch control
US4088305A (en) * 1976-12-17 1978-05-09 Caterpillar Tractor Co. Brake-one way winch

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3152968C2 (de) * 1981-09-11 1993-10-07 Caterpillar Inc Steuersystem mit selektiver Druckunterteilung

Also Published As

Publication number Publication date
SU1074400A3 (ru) 1984-02-15
EP0019352A3 (en) 1981-02-18
WO1980002446A1 (fr) 1980-11-13
JPS56500421A (fr) 1981-04-02
JPH025680B2 (fr) 1990-02-05
EP0019352A2 (fr) 1980-11-26
DE3068492D1 (en) 1984-08-16

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