HU208569B - Telemotor - Google Patents

Abstract

The subject matter of the invention is a telemotor, for example for actuating the shutter of motor valves, the drive element of which can control corresponding displacements. The essence of the invention consists in the fact that the telemotor is equipped with a digital control (S) which has at least two control members which permit the predetermined displacements (x1, x2, xn) of the drive element (4, 17, 31) of the telemotor between the two end positions. <IMAGE>

Description

The present invention relates to a telemotor for actuating, for example, a shut-off device for motor valves or the like.

As is known, "telemotors" are, for example, cylinders widely used in hydraulic or pneumatic systems. For example, hydraulic cylinders contain a constant amount of fluid acting as a "hydraulic link" between their piston and the hydraulic elements that control it (e.g., check valves), where this fluid, when pressurized, transmits the energy required for actuation.

Although these cylinders are widely and versatile in use, they have practically only two end positions. One is the "0" position with no pressure (single acting cylinders) or fully pushed, and the other end position with full stroke, ie the fully extended "1" position. Thus, these cylinders occupy only a clearly defined position in their two end positions. Consequently, either as an actuator or as an actuator of the actuators, they can only be used to implement control situations corresponding to their two end positions.

Otherwise, actuators are used in control technology which have a plurality of intermediate positions between their two end positions, in which they can function normally. These include hydraulic or pneumatic control valves, electric control resistors, etc.

For example, for hydraulic control of the cylinders, AT 358347 proposes a solution whereby it attempts to hydraulically adjust a continuous actuator by varying the relationship between the piston and the piston rod. Thus, this solution only moves the problem to change the relationship between the piston and the piston rod, but with little success.

For the same purpose, a complicated and expensive control valve system is disclosed in DE-OS 1921977 and DEOS 2,244,445. Furthermore, DEOS 2725917, which in turn proposes a five-chamber check valve, but DE-OS 3235784 proposes a check valve integrated with a solenoid valve, is intended to solve this problem by a very complex design.

A common feature of the above solutions is that they result in highly complex and uncertain structures for which the accuracy of the setup is highly uncertain.

GB 1 401770 and GB 2,049,824 also disclose solutions in which the telemotor is provided with a digital control consisting of hydraulic cylinder piston units. According to the above two documents, these are hydraulic cylinder piston assemblies of the same diameter and stroke, which, as controls, are intended to actuate the telemotor actuator unit by one or more times its unit value.

In practice, there is often a need for the telemotor to be able to adapt not only to single or multiple increments, but also to adapt the device flexibly to the actual control movements. However, this need cannot be met by the currently known solutions, since known digital controllers would have to increase the number of cylinders of the same diameter and stroke to the extent that is physically impossible in the available space, and there are economic and rational limits to increasing the number of control units. these aspects severely limit their applicability.

It is an object of the present invention to overcome the above disadvantage, that is, to provide an improved telemotor which, while being relatively simple and inexpensive in design, with high adjustment accuracy, enables the digital control to provide the actuator step-by-step approach.

In order to solve this problem, we have started from the solution of the latter British patent. It is an object of the present invention that, if the cylinder piston-like unit is designed as a hydraulic cylinder, at least three pistons associated with the cylinder working space are provided which have the same strokes but different diameters and / or different strokes.

According to the present invention, the telemotor may also be designed as a pneumatic cylinder having at least two collapsible tanks, preferably balloons, in the working space adjacent to the plunger, each connected to a pneumatic pressure receptacle via a control valve.

According to the present invention, it is also possible to have a cylindrical piston assembly consisting of telescopically push-in electromagnets, wherein the weapon disposed axially displaceable in the retracting coil of the external electromagnet has a disposed axially disposed axle.

This is also the actuator of the telemotor, and the feed coils are connected to the excitation voltage source via a switch.

The invention will now be described in more detail with reference to the accompanying drawings, in which some exemplary embodiments of the present invention are illustrated. In the drawing:

Fig. 1 is a schematic diagram of a first embodiment of a telemotor according to the invention;

Figure 2 is a variant of the solution of Figure 1;

Figure 3 is a further version of a telemotor designed as a hydraulic cylinder;

Figure 4 is a schematic diagram of a telemotor designed as a pneumatic cylinder;

Figure 5 is a diagram of the electromagnet of the telemotor according to the invention.

In the drawing, similar details are denoted by the same reference numerals.

Figure 1 shows a telemotor of variable cross section but with same stroke transmitting cylinders. Here, the telemotor (1) is designed as a working cylinder, the cylinder (2) of which has a piston (3) which is displaceable axially. The piston rod (4) (4) can move within the stroke ("x") of the piston rod ("4") to control a unit, not shown here, such as the shut-off valve of the shut-off valve.

According to the invention, the telemotor is provided with digital (S) control. In this case, cylinders (5, 6 and 7) cooperate with cylinders (2) in which different pistons (8, 9 and 10) of different diameters (D _b D ₂ and D ₃ ) but with the same stroke (H) sliding. The pistons (8-10) are associated with an actuator cylinder (11, 12, 13, respectively), which in this case is a double-acting hydraulic cylinder.

The working area of cylinder (2) is designated by (14), which is filled with hydraulic fluid, such as hydraulic oil, as well as cylinders (5-7).

In the case shown in Figure 1, only three cylinders and the associated pistons are shown, but of course the number may be arbitrary depending on the particular application. The effective diameter (D 1 -D ₃ ) of the cylinders (5-7) and the pistons (8-10) in this case has the following relationship:

Dj: Dj + 1 = 1: (k) ⁰⁵ where k = 2.

Thus, the ratio of the selected diameters according to k = 2 to the telemodom of Figure 1 is as follows:

Dj: D ₂ : D ₃ = 1: 7Σ: 2.

The minimum volume of liquid to be added is the usable volume of cylinder (5):

D? x π x HV, = —-— ¹ 4

The useful volume (V ₂ ) of the cylinder (6) is twice that and the useful volume (V ₃ ) of the cylinder (7) is four times greater.

By pushing a single volume of debris into the working space (14), the piston (3) and the

V, (4) is the axial displacement of the piston rod (x) = - g, where F ₃ denotes the useful surface of the piston (3). If this displacement is y by the choice of dimensions, the following alternatives are possible between the positions of the cylinder (11-13) and the piston rod (4):

13 12 11 (3) 4 displacements 0 0 0 0 0 0 1 m / 7 0 1 0 2m / 7 0 1 1 3m / 7 1 0 0 4m / 7 1 0 1 5m / 7 1 1 0 6m / 7 1 1 1 7m / 7 = m

It can be seen from the table above that for binary control, three piston cylinders (11, 12 and 13) can be used to control piston (3) and piston rod (30) in eight different operating positions. Generally speaking, if the number of cylinders "n" were used, then k ⁿ , that is, in this case, position 2 could be created with very high adjustment accuracy.

Thus, in the embodiment of Fig. 1, the uncompressed fluid is to be operated as a hydraulic "bar", whereby the control displacement is a function of the amount of fluid introduced and the diameter of the piston (3). These liquid dosages may optionally be in the form of a specific function relationship. By increasing the number of transmitter elements and determining the volume change caused by the smallest transmitter element in a relatively small volume relative to the piston diameter, the piston (3) can be dropped in virtually any desired position between its two end positions. The actuators for the pistons (845 10) are preferably actuated by two end positions, i.e. digital actuators, such as hydraulic cylinders.

Fig. 2 shows a variant of the telemotor of Fig. 1, in which the cylinders (5-7) and the associated pistons (8-10) have the same diameter (D) but the cylinders (11-13) which actuate them (H) _b H ₂ and H ₃ ) strokes are different. The relationship between strokes in this case is as follows:

H _; : H; ₊ j = 1: k, where k = 2.

Here, the cylinders (11-13) are double-acting hydraulic cylinders. Note, however, that these could be single-acting cylinders. However, in this case, for example, a compression spring (15) would have to be used to move the piston (3) to its internal end position.

HU 208 569 Β

In the arrangement of Figure 2, the stroke rate was selected as follows:

H: H ₂ : H ₃ = 1: 2: 4.

The mode of operation of the telemotor of Figure 2 is the same as that of Figure 1.

If a larger number of cylinders are to be displaced, they may optionally be connected to a separate fluid reservoir, the fluid-filled interior of which may be connected by a separate tube (not shown). This would have the advantage that the controls and workers of the telemotor can be easily separated. This arrangement may be particularly advantageous when the telemotor has a relatively small installation space.

The telemotor of Figures 1 and 2 can be advantageously used, for example, in machine tools, for positioning structural units, or, for example, for actuating pipe closures in motorized valves, even when the valve performs a control function. In addition, the telemotor of the present invention is capable of controlling any actuator in control circuits or control systems.

The telemotor of Figure 3 may be considered as a further embodiment of the solution of Figure 1. Here, the pistons (8-10) are guided directly into the openings of the cylinder (2) and can be inserted directly into the working space (14). Here, the cylinders (5-7) are omitted, and the pistons (8-10) have a long-rimmed, spike-like configuration.

The volume of the pistons (8-10) is shown in Fig. 3 (V _b V ₂ and V ₃ ), respectively.

In the embodiment of FIG. 3, similarly to FIG. 1, the pistons (8-10) have different diameters (D _b D ₂ D ₃ ), but the strokes (H) are the same.

In this case, the relationship between the volumes (Vj-Vj) of the pistons (8-10) is chosen as binary, i.e. V ₂ = 2'xV,

V ₃ = 2xV ₂ = 2 ² xV,

V _n = 2xV (nl) = 2 ⁿ -'xV ₁ .

The fully pushed piston (8) thus displaces (VJ) the volume from the working space (14) and consequently, through the hydraulic transmission, puts the piston (3) and its associated piston rod ("0") into its initial position (x 0). pushing the piston (9 or 10) individually or in any combination, the displacement (x) of the piston rod (4) depends on the sum of the piston volumes pressed simultaneously.

Since the number of pistons may, in principle, be any number (n), the displacement of the piston (3) for displacement of the pushed pistons (V) can be determined from the following relationship:

x = KxV. where:

- V (piston) volume,

- K denotes a geometric constant.

The operating variants for the selected binary code are listed in the following table:

1 2 ... n V X 2 ° 2 '... 2 ^n-1 <- binary code I the position of the spikes 0 0 ... 0 0 0 1 0 ... 0 V KxVj 0 1 ... 0 V ₂ KxV ₂ = 2xKxV, 1 1 ... 0 v ₁₊ v ₂ Kx (V! + V ₂ ) = 3xKxVj 1 1 ... 1 n Σν> i = l f ⁿ Ί kx £ ^v í = i = l V 7 = (2 ⁿ -l) xKxVl

Based on the above, the resolution is as follows:

a = X _i -X _(i _ ₁ ) = KxV _b where (i = 2 ... n)

This means that with proper control of the pistons, any position between x = 0 and x = x _max ("a") can be adjusted step by step with the piston rod (4). The maximum displacement in this case is:

x _max = (2 ⁿ -l) xKxV,.

If, in the exemplary embodiment of Fig. 3, the nominal inside diameter of cylinder (2) is taken as 50 mm and the value of "n" is set to 8, then x _max = 1.02 mm; a = 0.004 m; and achievable accuracy of 0.4%

If n = 16 for the same cylinder size, then x _max = 262.14 mm; a = 0.004 mm; the available accuracy is 0.002%.

The above examples illustrate the very high accuracy of the telemotor of the present invention.

Figures 4 and 5 illustrate two further exemplary embodiments of the present invention.

In Figure 4 the full pneumatic motor (16) cylinder, which is connected (17) piston (18) piston ₍₁₆₎ axially movable cylinder. In the working space (19), which is unidirectional to the piston (18), two or more, in this case three, inflatable (expandable) diaphragms or balloons are arranged axially adjacent to one another. In the present case, balloons (20, 21 and 22) are used which, when inflated or lowered, can be displaced axially by displacement of the piston (18). Each of the cylinders (20-22) is connected via a remote-controlled valve (23, 24, 25) to a container (26), which in this case contains compressed air. By changing the volume of the cylinders (20-22), the piston rod (17) can make a wide range of displacements between the two end positions.

Finally, Figure 5 illustrates a variant of a digital copper-controlled telemotor according to the invention, which is formed by two or more electromagnets arranged in a telescopic manner. In the illustrated case, the insertion coil (28) of the outer fixed housing (27) has an axially displaceable arm (28 _A ).

HU 208 569 Β arranged. This includes the retaining coil (30) of the electromagnet (29) in which the arm (31) is axially movable. The displacement of the end of the armor (31) also constitutes the displacement (x) of the telemotor control. The feed coils (28 and 30) can be connected to the exciter supply voltage via a switch (32 or 33).

The switch (32) closes at the (28) pulls the pull-in winding ₍₂₈₎ together with the armature and electromagnet (29) and the extended end position shown in Figure 5. When the switch (33) is closed, the retractor (30) retracts the armature (31) to its internal end position. Thus, the resultant displacements (x) can be achieved by operating the switches (32 and 33) individually or in combination.

Finally, it will be appreciated that many other variants or combinations of the digital controlled telemotor of the present invention may be contemplated within the scope of the claimed application. For example, the outgoing displacement (x) may not only be linear, i.e. linear, but may also be predetermined. This increases the scope of application. Finally, it is emphasized that "digital" (S) control refers to any two-state control that only permits "0" and "1" positions.

Claims (3)

PATENT CLAIMS A actuator for actuating a shut-off device of a telemotor, e.g. which is provided, as a control, with at least three pistons (8, 9, 10) cooperating with the working space (14) of the cylinder (2) having the same stroke (H) but different diameters (Dj, D ₂ , D ₃ ), preferably the ratio is 1: 7Σ: 2 or the pistons (8,9,10) have the same diameter (D) but their strokes (H _1; H ₂ , H ₃ ) are different, preferably 1: 2: 4. Priority: 1988.05. 11th 2. The actuator for actuating the shut-off mechanism of a telemotor, e.g. having a piston rod (18) axially displaceable in a cylinder (16 _A ), connected thereto by a piston rod (17) forming the actuator of the telemotor, and in the working space (19) of the working cylinders (16) partially bounded by the piston (18); as control means, at least two collapsible tanks, preferably balloons (20, 22), are arranged one after the other, each connected to a pneumatic pressure receptacle (26) via a control valve (23, 25). Priority: 1988.05. 11th 3. The actuator for actuating the shut-off device of a telemotor, e.g. 27, 29), wherein a coil (30) of the other electromagnet (29) is disposed in the coil (28 _A ) of the outer electromagnet (27), which is axially displaceable, and the coil (31) thereof is also axially displaceable, and this is also the actuator of the telemotor, and the feed coils (28, 30) are connected to an excitation voltage source via a switch (32, 33) (modification priority 04/05/1989).