摘要:
Eine Steuereinrichtung ist für eine hydraulisch betätigte, mit einem Federspeicherbremszylinder (2) als Bremszuspanneinrichtung versehene Feststell- und/oder Notbremseinrichtung (1), vorzugsweise eines land- oder bauwirtschaftlich nutzbaren Traktors oder Systemfahrzeuges vorgesehen. Die Steuereinrichtung dient zur Steuerung des Druckes in einem Druckraum (4) des Federspeicherbremszylinders (2), wobei sie zwischen diesem und einer Druckquelle (9) angeordnet ist und ein als Wegeventil ausgebildetes, elektronisch in zwei unterschiedliche Schaltstellungen aktuierbares Bremsbetätigungsventil (16) aufweist. Dabei wird das Bremsbetätigungsventil (16) über eine elektronische Steuereinrichtung (20) betätigt. Zur Gestaltung des Bremsbetätigungsventils (16) derart, dass dessen Steuerschieber ohne Rastmittel, die zusätzlich zu dessen Stelleinrichtung vorzusehen sind, in der zuletzt eingenommenen Schaltstellung gehalten wird, soll eine Stelleinrichtung (18) des Bremsbetätigungsventils (16) derart ausgebildet sein, dass diese das Bremsbetätigungsventil (16) in zumindest einer seiner Schaltstellungen eigenstabil hält, so dass dessen Steuerschieber ohne eine weitere Bestromung der Stelleinrichtung (18) in einer zuletzt eingestellten Schaltstellung verbleibt.
摘要:
An object is to reduce a load acting on an engine upon starting up the engine such that the engine can be quickly started up to reliably feed pressure oil from a hydraulic pump to an accumulator. A hydraulic control system is provided with first accumulators (24,25) connected to a hydraulic pump (23) via a first line (28) and second accumulators (26,27) connected to a second line (29) branching from the first line (28), an on/off valve (32) arranged in the second line and interposed between the first line (28) and the second accumulators (26, 27), an operation detection device (41) for detecting whether or not a starter (22) is in an operation state, a rotational frequency detection device (a rotary encoder (47) and rotational frequency calculation device (43)) for detecting a rotational frequency of an engine (21), and a valve control device for, upon detection of the operation state of the starter (22) by the operation detection device (41), controlling a valve position of the on/off valve (32) at a closed position until the rotational frequency reaches an idling rotational frequency set beforehand but then controlling the valve position of the on/off valve (32) at a closed position.
摘要:
A hydraulic power braking circuit for a vehicle has a reservoir (23) for hydraulic fluid and a pump (14) which draws hydraulic fluid from the reservoir for charging a hydraulic pressure vessel (13) with pressurised fluid. A driver operated pilot valve (11) is provided for directing pressurised fluid from the pressure vessel (13) to open a relay valve (15) which connects the pressurised fluid to brake actuators to apply associated brakes (18). The pilot valve (11) and relay valve (15) both having return lines (21, 22) to dump fluid to the reservoir (23) when not operating the relay valve or brake actuators respectively. Both return lines (21, 22) have U-shaped end configurations (25, 24) within the reservoir (23) which ensure that the ends of these return lines retain fluid therein no matter what inclination of the reservoir occurs during use of the vehicle to avoid the entry of air into the circuit. This arrangement allows the reservoir to be located below the pilot and relay valves without the risk of air entering the system.
摘要:
The valve (1) comprises body means (2) having a first seat (7) wherein a first cursor (4) is received that has a first end (206) protruding from said body means (2) and is slidable in a first direction, a second seat (13) in said body means (2) that has an outlet (9) for a fluid and wherein is received a second cursor (11) that has a second end (111) protruding from said body means (2) and is slidable in a second direction, connecting conduit means (209) that connects said first seat (7) and said second seat (13), said first (4) and second cursor (11) being conformed in such a way as to check in respective axial positions a passage of said fluid from said first seat (7) to said second seat (13) through said connecting conduit means (209) contrasting means (16) acting on said second cursor (11) in such a way as to contrast a shift of said second cursor (11) in said second direction.
摘要:
The invention relates to a brake device (1) for a construction machine, comprising a first brake circuit (2), which is coupled to a first brake member (4) on a first wheel axle (6) of the machine, a second brake circuit (8), which is coupled to a second brake member (10) on a second wheel axle (12) of the machine, the first and second brake circuits (2, 8) being independent of one another, a pressure source (14) for hydraulic oil, which is coupled to the first and second brake circuit (2, 8), and a brake valve (16, 16'), which is coupled to the first and second brake circuit (2, 8), which brake valve (16, 16') is designed to control the hydraulic oil from the pressure source (14) to the brake members (4, 10) on the wheel axles (6, 12). The first or second brake circuit (2, 8) comprises limiting elements (18, 42'), which limit the pressure and/or flow of hydraulic oil when the brake valve (16, 16') controls the hydraulic oil from the pressure source (14) to the brake members (4, 10) on the wheel axles (6, 12).
摘要:
The invention relates to an inching braking device. According to the invention, an adjusting device (90, 92) first initiates an adjusting movement of the brake piston (12) of a brake valve system (6, 8) after a predetermined stroke of a driving element (18, 68, 70), said driving element being provided for an inching piston (14). By appropriately selecting the axial length of the pins (68, 70) and of the stroke (H) and by correspondingly matching the springs, it is possible for the brake pressure pB to begin to increase before the inching pressure pI falls to zero.
摘要:
Mechanically controlled power transmission device comprising a rotary engine driving, through a lever (3) and a clevis, (5), a hydraulic slide valve (1) which consists, in a known manner, of a rod (6) sliding in a hole (7) and includes blocks (P1, P2) capable of selectively establishing communication between firstly a user device (U) and secondly a high pressure source (H) or an outlet (E). Two springs (R1, R2) act on the slide valve in opposite directions, return the latter, in the event of a breakdown, into a neutral position which is preferably a position in which no communication is established. The device of the invention is for use in the motor car industry.
摘要:
Mechanically controlled power transmission device comprising a rotary engine driving, through a lever (3) and a clevis, (5), a hydraulic slide valve (1) which consists, in a known manner, of a rod (6) sliding in a hole (7) and includes blocks (P1, P2) capable of selectively establishing communication between firstly a user device (U) and secondly a high pressure source (H) or an outlet (E). Two springs (R1, R2) act on the slide valve in opposite directions, return the latter, in the event of a breakdown, into a neutral position which is preferably a position in which no communication is established. The device of the invention is for use in the motor car industry.
摘要:
A method of controlling hydraulic braking pressure in a vehicle, wherein an electrically operated actuator (4) produces a hydraulic braking pressure F′OUT(n) in response to an applying electricity level FOUT(n) applied to the actuator (4), such that the hydraulic pressure F′OUT(n) increases as the applying electricity level FOUT(n) increases, includes the steps of setting the applying electricity level F′OUT(n) in correspondence to an amount of braking operation FOUT(n), determining at least two types of electricity levels F′OUT(n) having larger and smaller variation rates with respect to a variation in an amount of braking operation FOUT(n), and changing the applying electricity level F′OUT(n) having the larger variation rate to an applying electricity level F′OUT(n) having the smaller variation rate, when the amount of braking operation FOUT(n) is greater than or equal to a switchover set value FOUT.O.