JPS623321B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A multi-position actuator having multiple positions disposed within a cylinder, the actuator being responsive to a predetermined pressure applied thereto;
A multi-position actuator is disclosed that is adapted to be moved a predetermined distance in steps. One or more of the plurality of devices are selectively actuated to cause fluid pressure to be applied to one or more of the pistons, depending on which of the devices is actuated. The output element is driven by the actuated piston.

In some applications, in response to a particular pressure,
It may be desirable to have a pneumatic or hydraulic cylinder step into particular positions. Many pressure position actuators currently in use, after they have been moved to the desired position,
A delicate balance is used to ensure that they remain in their set positions. Such balance devices are often subjected to changes in actuation forces that change their position.

One area where it is desirable to maintain a particular position of a driven member is in manual throttle operations used to control the speed of vehicles such as railroad cars. It is generally desired to maintain some selected throttle position and speed after the vehicle begins moving.

In many multi-car rail systems without locomotives, the drive means is included in each car. In a multi-car rail system that includes more than one vehicle using a diesel engine, each vehicle may include one or more engines. Typically, the driver operates a single manual control to control the throttle or speed of all engines.

Quite often, contamination and other conditions associated with throttle control will cause the final degree of control for individual engines to differ. When this happens, the engines produce different power outputs, with one engine working and the other not. In order to ensure a more uniform speed of the railway vehicle and greater efficiency of operation of the drive engines, it is preferred that all of the throttles driving all of the engines are actuated in substantially the same way.

One object of the present invention is to provide an improved means for moving an element to a particular predetermined position in response to the application of a particular predetermined pressure.

Another object of the invention is to provide an improved pneumatic or hydraulic positioner.

It is a further object of the present invention to provide an improved throttle control mechanism for a railroad system including a plurality of individually driven vehicles.

According to the invention, the multi-position device comprises:
It responds to multiple different pressures applied to it. A pressure-responsive device is configured such that the multi-position device is moved in discrete steps depending on which pressure-responsive device is actuated in response to discrete pressure levels applied to it. Let it be. The multi-position device includes:
It includes a plurality of separate pistons, each having a rod connected thereto, and arranged to displace an adjacent piston. A control element, which may be a throttle on a railway vehicle, is caused to move in individual steps in response to the maximum movement of these pistons.

Other objects and advantages of the invention will become apparent to those skilled in the art upon reading the following claims and specification in conjunction with the accompanying drawings.

An overall system in which the invention may be used is shown in FIG. The illustrated system may be relevant to a railroad vehicle in which the operator controls speed by manually operating a controller to control the position of the throttle. The throttle is moved to different positions to control the pressure of a fluid, such as air, applied to control the speed of the engine driving the railroad vehicle.

The air reservoir 10 is connected to a supply air control or air pressure regulator 12 . Air pressure regulator 12
is operated by the driver by manually moving the handle 14. Air is provided from conduit 16 to a flexible pipe or conduit 18, which communicates pressurized air to a pressure responsive device, which may include a valve assembly 20. As mentioned later,
Various output air pressures are provided from valve assembly 20 and communicated to multi-position controller 22 . The details of the valve assembly 20 and multi-position controller 22 and their operation will be described in detail in connection with the other figures.

Output air pressure from conduit 16 is also provided to brake control unit 23. This allows a single throttle or pressure regulator control to be used for speed control and brake control. The details of the brake system are not described in detail or shown, since they are only secondary to the invention.

The multi-position actuator 22 is
The throttle lever 26 is connected to an arm 24 which is connected to a throttle lever 26;
The lever 26 is moved according to the pressure applied to the actuator 22. Throttle 2
5 is controlled according to the position of arm 24 and throttle lever 26. Actuator 2
Action 2 causes arm 24 and throttle lever 26 to move to the position shown by the dotted lines. Arm 24 and throttle lever 26
The degree of movement of determines the power output from the drive shaft 28 being driven by the engine 30.
Throttle 25, controlled by arm 24 and throttle lever 26, may control the amount of fuel provided to control the speed of engine 30. Such means are well known and, as they are not directly relevant to the present invention, will not be described in detail.

Referring to FIG. 2, pressure responsive device 20 in one preferred embodiment includes a plurality of bistable valve assemblies 32, 34, 36 and 38. Conduits 40, 42, 44 and 46 lead from the valve assembly to pressure chambers 48, 50, 52, 54. These pressure chambers are formed within the cylinder 63 between adjacent pistons 56, 58, 60 and 62. The openings 64, 66, 68 and 70 are
The pressure chambers between each piston communicate with conduits 40, 42, 44 and 46.

As shown in FIG. 2, air from the air reservoir 10 and air pressure regulator 12 is communicated to conduit 16 and via appropriate branch conduits 17 to bistable valve assemblies 32, 34, 36 and 38. given to each of them. As discussed below, each valve is designed to operate at different pressure levels, preferably sequentially as the pressure gradually increases from a low level to a high level, so that certain The actuation of a particular valve or valves depends on the amount of fluid pressure applied to them. The number of actuated bistable valve assemblies controls the number of actuated pistons and arms 24
and throttle lever 26 (FIG. 1), which ultimately control the speed of engine 30.

With particular reference to FIG. 3, the operation of multiple pistons 56, 58, 60 and 62 within cylinder 63 is shown. Figure 3a shows the spring 8
4 shows the piston in an inoperative position biased towards the left with respect to stop pieces 76, 78, 80 and 82. Each of the pistons 56, 58, 60 and 62 has a respective arm 56', 58', 60' and 62' (FIG. 2), each arm engaging an adjacent piston located to the right of the respective piston. It is designed so that it can be moved together.

When fluid enters the pressure chamber 48 behind the piston 56 through the opening 64 and exceeds a certain pressure that overcomes the biasing force of the spring 84, the piston 56 disengages from the stop piece 76 and closes the stop piece 78. Move to the right until you reach it. piston 56
When moving to the right, it forces all other pistons 58, 60 and 62 to the right by their mutually abutting arms 56', 58' and 60'. This situation is shown in Figure 3b.

When fluid enters the pressure chamber 50 behind the piston 58 and exceeds a predetermined level sufficient to overcome the biasing force of the spring 84, the piston 58 leaves the stop piece 78 until it reaches the stop piece 80. Move to the right until At the same time, pistons 60 and 62 are also moved to the right by the arms connected to each piston. This situation is shown in Figure 3c.

Similarly, the pressure chamber 52 behind the piston 60
When the fluid pressure within increases above a certain level which further overcomes the biasing force of spring 84, piston 60 moves to stop piece 82 and piston 62 also moves to the right. This situation is shown in Figure 3d. Although FIG. 3 shows the final stepped position, it is contemplated that this design may further include non-stepwise movement of the piston 62. The arm 62' of the piston 62 is
It may be the same member as the arm 24 or may be connected thereto. It is then connected to the throttle lever 26 of FIG.

It will be appreciated that this cylinder 63 is a multi-position actuator in which the stops are positioned such that each piston can travel a greater distance than the piston behind it. Each piston has a rod or arm of sufficient length to push the piston to its right.

Referring to Figures 4a and 4b, the piston 5
a bistable valve assembly 32 communicating with a pressure chamber displacing 6, 58, 60 and 62 (FIG. 2);
34, 36 and 38 are shown. Fourth
Figure a shows one of these valve assemblies in an inoperative position, and Figure 4b shows that when fluid is applied to it in excess of a predetermined pressure level,
The valve assembly is shown in the actuated position.

Referring to FIG. 4a, poppet valve 32
includes a housing 90 having an opening 92 for receiving pressure from conduits 16 and 17 (FIGS. 1 and 2);
have. Diaphragm 94 divides housing 90 into an upper chamber 96 and two lower chambers 98 and 99.

Poppet 100 is biased by spring 102 and normally maintains diaphragm 94 in the lower position shown. The amount of biasing force of spring 102 can be adjusted by adjustment screw 104. The upper chamber 96 has one breathing opening 106.

When the controlled pressure from the air conduit 16 (FIGS. 1 and 2) is not sufficient to overcome the pressure of the bias spring 102 and is below the predetermined level, the cylinder pressure is discharged downwardly through the exhaust opening 110. It is discharged to the atmosphere via chamber 99.

When the pressure from conduit 16 (FIGS. 1 and 2) exceeds the predetermined value and that pressure is applied through opening 92, poppet 100 suddenly rises as shown in FIG. 4b. Move to second position. Diaphragm 94 also rises. This closes the exhaust opening 110 and causes its pressure to be applied to the pressure chamber behind the associated piston through the opening 112, actuating the piston as described above.

In one embodiment of the invention, one of the valves of the type shown in Figures 4a and 4b is mounted on cylinder 63.
(FIG. 3) are attached by bolts to respective openings leading to pressure chambers behind a plurality of pistons disposed within. The four valves shown are
Of course, it can also be incorporated into an integral valve assembly unit 20.

With reference to Figures 5 and 6, the pressure and area 11
When the product of 4 exceeds the spring force associated with that poppet valve, the poppet 100 begins to rise, opening the pressure opening 112 and opening the exhaust opening 11.
0 (Figures 4a and 4b). At this time, the area of the poppet 100 increases by an area of 118,
Area 116 is reduced. The pressure to close the valve is determined by the difference between area 118 and area 116, which is somewhat less than the pressure to open the valve.

To explain FIGS. 5 and 6, reference is made to FIG. 7, which shows the operative portion of the poppet 100 of FIGS. 4a and 4b. The valve has been partially removed and the diaphragm is not shown.

At pressures below the predetermined level, the poppet is lowered. The pressure is applied upwardly against a surface 120 corresponding to area 114 in FIG. When the pressure increases enough to raise the poppet, additional upward pressure is applied to surface 122. This can be thought of as area 118 in FIG. At the same time as the poppet is raised,
A downward pressure is applied to surface 124.
This is the area 116, which is used in determining the total upward pressure on the poppet 100.
Area 118 must be subtracted from surface 122.

Thus, the present invention is useful in railroad vehicles that have a single engine and where it is desirable to use a relatively small cylinder where very small changes in throttle control position can result in large changes in engine speed. It will be appreciated that the invention provides a multi-position actuator that can operate reliably. The invention may be applied to multi-engine systems having multiple throttles controlled by a single control mechanism. In the latter case, the friction and contamination associated with the throttle will rarely cause the engines to produce different power outputs, with one engine running and the other not contributing. do not have.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram, a portion of which is shown as a block diagram, illustrating one embodiment of the present invention. Second
1 is a partial block diagram of some of the main elements of FIG. 1 illustrating the operation of the present invention. Figures 3a, 3b, 3c and 3d illustrate a multi-position device of the type embodying the invention.
Figure 2 shows different operating positions of the device. Figures 4a and 4b illustrate different operating positions of a pressure responsive device of the type that may be used in practicing the invention. Figure 5 shows 5 in Figure 4b.
FIG. 5 is a cross-sectional view taken along line -5. FIG. 6 is a cross-sectional view taken along line 6--6 of FIG. 4b. FIG. 7 is a diagram illustrating the main parts included in the device shown in FIGS. 4a and 4b for the purpose of explaining the operation of the device. Explanation of symbols 10: Air reservoir, 12: Air pressure regulator, 14: Handle, 16: Conduit, 17: Branch conduit, 18: Conduit, 20: Valve assembly, 22:
Multi-position actuator, 23: Brake control unit, 24: Arm, 25: Throttle, 26: Throttle lever, 28: Drive shaft, 30: Engine, 32, 34, 36,
38: Bistable valve assembly, 40, 42, 44,
46: Conduit, 48, 50, 52, 54: Pressure chamber,
56, 58, 60, 62: Piston, 56', 5
8', 60', 62': Arm, 63: Cylinder,
64, 66, 68, 70: Opening, 76, 78, 8
0, 82: Stop piece, 84: Spring, 90: Housing, 92: Opening, 94: Diaphragm, 9
6: Upper chamber, 98, 99: Lower chamber, 100: Poppet, 102: Spring, 104: Adjustment screw,
106: Breathing opening, 110: Exhaust opening, 112:
Opening, 114, 116, 118: Area, 120,
122, 124: Surface.

Claims (1)

[Scope of Claims] 1. A multi-position hydraulic actuator characterized by: (a) one pressurized fluid source 10; and (b) one hydraulic manual actuator connected in series with said pressurized fluid source. (c) in parallel with said hydraulic manual control means, each having one inlet and one outlet, for receiving pressurized fluid in each inlet via a branch conduit; a plurality of connected bistable fluid operated valves 32, 34, 36, 38; (d) each of said bistable fluid operated valves is provided with the associated bistable fluid operated valve normally inoperative; biasing means 10 for conducting the pressurized fluid to the output opening when the pressurized fluid introduced from the inlet exceeds a predetermined pressure;
(e) provided in each of said biasing means;
(f) one cylinder 63; (g) arranged from the first end to the second end of the cylinder; Multiple chambers in the cylinder 4
(h) a plurality of pistons 56, 58, 60, 62 forming a plurality of chambers 8, 50, 52, 54; a plurality of openings 64, 66, 68, 70 respectively connected to the output openings of the stabilizing fluid actuated valve; a plurality of stop pieces 76, 78, 80, 82 arranged at intervals and alternating with said pistons and limiting the movement of each of said pistons; (j) one drive element 26; (k) disposed between the second end of the cylinder and a piston 62 disposed proximate thereto;
When the pressure in each said chamber exceeds a predetermined level, the associated piston is allowed to move toward the second end, and when the pressure in said chamber is below the predetermined level, the associated piston is directed toward the first end. (l) motion transmitting means 56', 5, provided on each of said pistons, for transmitting the movement of each piston to an adjacent piston or to said drive element;
8', 60', 62', and when pressurized fluid is conducted by the fluid pressure manual control means, the plurality of A drive means is actuated by communicating a pressurized fluid through one or more of the chambers to move a piston 62 disposed proximate the second end of the cylinder. 2. The apparatus of claim 1, wherein a bistable fluid operated valve 32 connected to a chamber adjacent the first end of the cylinder to a chamber adjacent the second end of the cylinder. A multi-position fluid actuator characterized in that the predetermined operating pressures thereof are set to successively higher pressures in order toward the bistable fluid actuated valves 38 . 3. A multi-position fluid actuator according to claim 1 or 2, characterized in that the bistable fluid operated valves 32-38 are poppet valves. 4. The multi-position device according to any one of claims 1 to 3, wherein the drive element 26 is a lever connected to a throttle of an engine of a railway vehicle. Fluid actuator.