Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/26—Generation or transmission of movements for final actuating mechanisms
  • F16H61/28—Generation or transmission of movements for final actuating mechanisms with at least one movement of the final actuating mechanism being caused by a non-mechanical force, e.g. power-assisted
  • F16H61/30—Hydraulic or pneumatic motors or related fluid control means therefor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/26—Generation or transmission of movements for final actuating mechanisms
  • F16H61/28—Generation or transmission of movements for final actuating mechanisms with at least one movement of the final actuating mechanism being caused by a non-mechanical force, e.g. power-assisted
  • F16H61/30—Hydraulic or pneumatic motors or related fluid control means therefor
  • F16H2061/304—Hydraulic or pneumatic motors or related fluid control means therefor using telemotors, i.e. systems with master cylinder and linked shift actuator without external pressure source

Definitions

• Hydraulic transmission of motion has many advantages, but leakage can lead to a loss of hydraulic medium with accompanying disadvantages in the form of reduced precision or possibly non-serviceability. Leakage can also lead to an undesirable relative displacement between the pistons in master cylinder and actuator cylinder with accompanying difficulties with regard to precision in transmission of motion as a result of mistiming between master cylinder and actuator cylinder.
• lost hydraulic medium can be replaced by hydraulic medium from a container being pumped in at different points in the system via check valves. Any mistiming between the cylinders can, however, not be corrected, but can instead gradually increase.
• mistiming between master cylinder and actuator cylinder can lead to blocking of the shift motion.
• This mistiming can arise, for example, as a result of one of the refilling check valves not closing as intended, or of leakage leading to changed volumes of hydraulic medium in the system. .
• Fig. 1 shows a schematic diagram of an arrangement according to the invention, with the two cylinders in neutral position;
• Figs. 2-5 show a detail of Fig. 1 with the two cylinders in different relative positions;
• Fig. 6 shows a detail of Fig. 1 in an embodiment as a gearbox for vehicles
• Fig.7 shows a detail of Fig. 1.
• an arrangement 1 includes a master cylinder 3 which is provided with an actuator member 2 in the form of a handle, for example, and which is hydraulically connected to an actuator cylinder 4, for transmission of motion from the actuator member 2 to a driver 5 connected to the actuator cylinder 4, which driver is in turn intended to act in a conventional manner on a further movable member (not shown here).
• a first chamber 6 in the master cylinder 3 forms, together with a first line 7 and a first chamber 8 in the actuator cylinder 4, a first hydraulic circuit 6-8.
• a second chamber 9 in the master cylinder 3 forms, together with a second line 10 and a second chamber 11 in the actuator cylinder 4, a second hydraulic circuit 9-11.
• FIG. 7 The more detailed embodiment of such a check valve can be seen from Fig. 7, in which the first piston 13 has the position shown in Fig. I .
• the hydraulic medium can in this case flow in the direction of the arrow 16 arid, via axial channels 17 and 18, arrive in the first chamber 6.
• This situation is obtained when the piston rod 15 is displaced to the right in the drawing.
• the piston 13 comes to be displaced to the right in relation to the piston rod 15, into a sealing position against a stop 19, as a result of which outflow from the first chamber 6 is prevented.
• the second piston 14 is of corresponding design.
• the first hydraulic circuit 6-8 is also connected to the hydraulic medium container 12 via a normally closed non-return valve 20.
• the second hydraulic circuit 9-11 is also connected to the hydraulic medium container 12 via a normally closed non ⁇ return valve 21.
• the non-return valves 20 and 21 are electrically controlled, each via a control line 22 and 23 respectively, which are fed from a common voltage source.
• Two switches 24 and 25 are connected in series in the control line 22 and, in a corresponding manner, two switches 26 and 27 are connected in series in the control line 23. All switches are cam-controlled and take up the open position when they are not activated.
• both the master cylinder 3 and the actuator cylinder 4 are in a centred neutral position, the actuator members of the switches 25 and 27 resting in a recess 28 in the piston rod 15 of the master cylinder 3, while the actuator members of the switches 24 and 26 rest in a recess 29 in the piston rod 30 of the actuator cylinder 4.
• the two non-return valves 20 and 21 are dead and in the closed rest position.
• the actuator cylinder 4 also comes to be centred, and if the actuator member 2 is guided to the left end position, the piston rod 30 comes to be guided to the right end position, still with the non- return valves 20 and 21 closed.
• the master cylinder 3 and the actuator cylinder 4 have become affected by mistiming and can no longer be centred at the same time.
• the non-return valves 20 and 21 still do not receive any voltage and are therefore closed.
• the actuator member 2 can only be guided a short distance to the left before the piston rod 30 reaches its-right end position and prevents continued motion of the actuator member 2.
• the switch 24 is closed.
• the piston rod 30 comes to be forced to the left, at the same time as the switch 25 closes, while the switches 26 and 27 are still open.
• the non-return valve 20 receives voltage and opens.
• the actuator member 2 is moved further to the right until the piston rod 30 has been centred and the switches 24 and 26 are thus open. From this position, the actuator member 2 is then instead guided to the left so that the position according to Fig.4 is obtained. In this connection, the switch 24 comes to close, as a result of which the non-return valve 20 receives voltage and opens.
• the piston rod 30 Upon continued motion to the left of the actuator member 2, the piston rod 30 remains close to its centred position because hydraulic medium can now leave the first hydraulic circuit 6-8 via the non-return valve 20.
• the second hydraulic circuit 9-11 now receives replenishment via the check valve at the second piston 14.
• the switch 25 opens again, with the result that the non-return valve 20 closes.
• the two cylinders are now both centred again and work in time.
• connection, according to Fig. 6, the actuator member 2 consists of a gear lever which is pivotably mounted in a conventional manner and with the aid of which the piston rod 15 can be displaced in the opposite direction to the direction of displacement of the gear lever.
• the driver 5 is in this connection designed as a gear actuator.
• 3rd or 4th gear can be engaged with the aid of the gear actuator.
• the type of switch described above can of course, within the scope of the invention, be replaced by other types of transmitter with different positioning, without changing the functioning of the arrangement.
• the type of check valve, for example, on the pistons 13 and 14 can also be changed.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)
• Fluid-Pressure Circuits (AREA)
• Control Of Fluid Gearings (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20378402

Family Applications (1)

Country Status (3)

Citations (3)

• 1990
  • 1990-01-31 SE SE9000326A patent/SE465477B/sv not_active IP Right Cessation
• 1991
  • 1991-01-17 WO PCT/SE1991/000031 patent/WO1991011639A1/en active Application Filing
  • 1991-01-17 DE DE19914190139 patent/DE4190139T/de not_active Withdrawn

Patent Citations (3)

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