US3363514A - Control and switching device in mechanically or hydraulically operated traverse-motion systems in spinning, spooling and especially ring twist machines - Google Patents
Control and switching device in mechanically or hydraulically operated traverse-motion systems in spinning, spooling and especially ring twist machines Download PDFInfo
- Publication number
- US3363514A US3363514A US450467A US45046765A US3363514A US 3363514 A US3363514 A US 3363514A US 450467 A US450467 A US 450467A US 45046765 A US45046765 A US 45046765A US 3363514 A US3363514 A US 3363514A
- Authority
- US
- United States
- Prior art keywords
- control
- piston
- switching
- choke member
- traverse
- 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 - Lifetime
Links
Images
Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01H—SPINNING OR TWISTING
- D01H1/00—Spinning or twisting machines in which the product is wound-up continuously
- D01H1/14—Details
- D01H1/36—Package-shaping arrangements, e.g. building motions, e.g. control for the traversing stroke of ring rails; Stopping ring rails in a predetermined position
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S60/00—Power plants
- Y10S60/911—Fluid motor system incorporating electrical system
Definitions
- the present invention relates to a control and switching device for hydraulically driven traverse mechanisms in spinning, spooling and, in particular, ring twist machines. More particularly, the subject invention relates to control and switching devices in which the directional change of the traverse stroke is caused by electrical end switches and wherein the movements of the working piston of the traverse drive temporarily undergo an acceleration as the amount of pressure fluid supplied to or led oii from the working cylinder per time unit is altered.
- the present invention therefore, has as its basic objective the bringing about of speed changes of the stroke movement in hydraulically driven traverse systems hydraulically, but without such templates, cam parts or other mechanical control means and without the drawbacks inherent in these.
- the present invention is based on the insight that for a traverse stroke of constant velocity there is required for the moving of the working piston a certain amount of pressure fluid likewise remaining constant in the time unit, and that for the increase of the speed of the working piston there is necessary in each case a certain additional amount of pressure fluid per time unit, which, however, should be Variable within wide limits for the great variety of possible traverse programs.
- the control and switching device in such a way that in the feed and drain system of the hydraulic working circuit between the pump with its appropriate path valve on the one hand and the two Working cylinder sides on the other hand there is switched parallel to the adjustable quantity regulators allocated to each of these sides an additional feed and drain line each with a controllable choke member or a choke member in common.
- the choke member or members can be made controllable by means of a hydraulic dosing device, tor example,'a measuring pump, an auxiliary amount regulator, an auxiliary choke member, or the like, which is preferably arranged in the return flow of the hydraulic control circuit of the choke member.
- this control circuit there can be provided, preferably, an electromagnetically operated control valve as, for example, a simple reversing slide.
- Such an arrangement makes it possible for the adjusting of the basic speed necessary in each case of the traverse movement by means of quantity regulators arranged in known manner in the feed and/or drain line system of the working cylinder to use simple chokes, slide valves, and the like as quantity regulators.
- the traverse speed can be altered at will by control of the flowthrough amount in the additional feed and/or drain lines engaged, according to the invention, parallel to the usual conduction system, by the method that the choke member provided in these lines, adjustable and possibly in common, is controlled, for example, in dependence on the working piston movement or according to a desired program.
- the choke member may be executed as control slide valve, quantity regulator, or the like.
- the control of the choke member takes place preferably over a hydraulic dosing device as well as an ordinary electromagnetic control valve which is operated by electric switching impulses in dependence on the time or, over limit switches, by the traverse program.
- an especially driven impulse generator or else the already present electric limit switches which cause the direction change of the traverse stroke can be used, indirectly or directly.
- one or several adjustable control switches may be allocated as impulse-givers for the choke member or choke members to the limit switches for the directional change of the traverse stroke, and this adjustable control switch or these adjustable control switches may be movable, if desired, directly or indirectly through the conveyor members which shift the limit switches for the directional change of the traverse stroke.
- the throughput capacity of the choke member engaged, according to the invention, parallel to the quantity regulator is fully utilized for the control of the traverse speed.
- the control intensity is here considerably more sensitive and precise than in those quantity regulator systems in which only a fraction of the throughput is controlled.
- the hydraulic displacement of the choke member in a hydraulically driven traverse system does not present, say, only a constructively more expedient and less space-consuming solution, but actually brings about, in contrast to the known rigid mechanical control mechanisms, the realization of the demand to make it possible in a simple manner during the course of the program to make corrections and to carry out any variations that may subsequently still be necessary in the winding structure. It is precisely this, however, which is decisive in practical use.
- control and switching apparatus operates entirely automatically according to a program settable at will, it nevertheless frequently occurs, for example, after a change in the winding form or type of distribution or in the material: or denier, that it is necessary during running operation to modify the course of the program, and to make corrections which may possibly be necessary by hand. This is now possible in a simple manner with the aid of the device according to the invention.
- FIGURE 1 shows the electro-hydraulic control and switching system in a ring twist machine
- FIGURE 2 shows the modified arrangement of the electric control and limit switch
- FIGURE 3 shows a form of the choke member in the hydraulic control system.
- the hydraulically driven traverse mechanism consists essentially of the ring rail 1, which is suspended on draw bands 2, which, in turn, are secured over deflection rollers 3 continuously with their other end on the piston rod 4 of the working piston 6, admitted on both sides, conducted in the hydraulic cylinder 5.
- the switching feeler 7 On the piston rod 4 there is mounted the switching feeler 7, Which operates the limit switches 8, 9 for the release of the stroke reversal and also special control switches 10, 11 as impulse generators for the control of the traverse speed, in which arrangement the switches are shifted by the threaded spindles 12, 13, acting as conveying members, of, for example, electrically controlled program adjusting system 14.
- Such a program adjusting system is described in detail in application Ser. No. 374,109 which was filed on June 10, 1964, the disclosure of which is incorporated herein by reference.
- the hydraulic working circuit of the traverse system consists of the pump 15 which conveys the pressure fluid from the supply tank 16 over the line 17 to the electromagnetically operated path valve 18.
- a manometer 2i To the line 19 branching from line 17 there are connected a manometer 2i and a pressure limiting valve 21 for the measurement and setting of the pressure prevailing in the hydraulic system.
- the switched-in zero position 22 of the path valve 18 is represented.
- the other switching positions are numbered 23 and 24.
- the lines 26-27 of the working circuit connect valve 18 with the two passages of adjustable choke member 28, which is represented in a special form of execution in FIG. 3 and is described in further detail below.
- the left-hand passage of the choke member 28 is connected through line 33 to line 32.
- Line 34 is connected to line 27 and leads over the permanently adjustable quantity regulator 35 or the nonreturn valve 36 arranged parallel to regulator 35 and the line 37 into the right-hand side of the working cylinder 5.
- Line 37 and the right-hand passage of the choke member 28 are connected with one another by line 38. From line 17 there branches off the control line 39 for the choke member 28 and leads into the valve 40 with its switching positions 41 and 42.
- valve the control line 43 leads into the left-hand side of choke member 28, while the right-hand side of choke member 28 is connected through the control line 44 with the control valve 40. From valve 40 the control line leads over the dosing device 45, for example, a settable and adjustable auxiliary quantity regulator, back into supply tank 16.
- dosing device 45 for example, a settable and adjustable auxiliary quantity regulator
- FIG. 2 there is shown a modified arrangement of the control and end switches.
- the limit switches 8 and 9 mounted on the spindles and conveyed through these carry sheet metal strips 46 and 47 with long holes 48 and 49, through which there are inserted screws 50 and 51, by means of which the control switches 10 and 11 are secured to sheet metal strips 46 and 47.
- the spacing between the limit switch 8 (or 9) and the control switch 10 (or 11) can be adjusted very easily and rapidly, while in the arrangement according to FIG. 1 it is first necessary to release a guide (not shown).
- FIG. 3 finally, shows the aforementioned choke member 28 in a special form.
- the control piston which consists essentially of three individual pistons 55, 56, 57 mounted at a distance from one another, which are solidly joined with one another by intermediate pieces 58, 59 of piston rod type.
- covers 52 and 53 there are provided central bores 66, 61 for connection to the control lines 43, 44 (FIG. 1).
- the ring-shaped cylinder chambers 62, 63, 64, 65 each have a connecting bore 66, 6'7, 68, 69 leading through the cylinder casing wall for the pressure fluid lines, 26, 27, 33, 38 of the hydraulic working circuit.
- profiled grooves or notches 72, 73 in the right-hand annular end surface 70, 71 of the individual pistons 55, 56 which form the connecting channels between the paired annular cylindrical chamber 62/63 or 64/65.
- FIG. 1 of the individual hydraulic switching and control elements are only schematically shown and are not intended to characterize any particular situation in the course of a given working program.
- a winding form with an approximately cylindrical middle portion and curved conical ends, the form and pitch of which is to be different.
- This winding form is caused by the fact that the relatively great traverse stroke of the ring rail, in relation to the total winding length, remains equal over the entire winding process and, from one end of the spool to the other, is slowly displaced during the entire winding process. In the process, the individual stroke has to be accelerated toward its ends.
- Means are provided for the formation of a thread reserve before the start of the winding process proper by means of individual or collective lowering of the spinning or twisting rings (not shown or described).
- the threaded spindles 12 and 13 have thread rising to the right and turn, according to the winding program here selected as an example, at equal turning speed and like direction, so that the limit switches 8 and 9 and also the control switches 16 and 11 move from right to left with constant spacing, until one of them is operated by a blocking switch (not shown) for the termination of the winding program.
- the degree of opening speed of choke member 28 depends on the setting of the auxiliary quantity regulator 45, through which the pressure fluid emerging from connection bore 60 of the left-hand chamber of choke member 28 flows over line 43 and control valve 40 (switching position 42) back into supply tank 16.
- auxiliary quantity regulator 45 determines the speed at which the passage cross sections of adjustable choke member 28 are opened and closed, and thereby the degree and the course of the acceleration and retardation of the movement of working piston 6 and ring rail 1.
- the carried-along switching feeler '7 runs over, in the back and forth passage, the control switches 10 and 11, and, namely, in each case immediately before the stroke reversal, for the purpose of the start of the acceleration, and immediately after the stroke reversal for the switching on of the functional readiness of the other control switch without further control function of its own.
- the proposed apparatus has the important advantage that any detectable deviations occuring during the winding process of the desired winding form can immediately be corrected by readjustment of auxiliary quantity regulator 45 and/ or of control switches 10 and 11.
- the control cams or plates under these circumstances must be dismantled and interchanged in a complicated manner, or reworked or even completely remade and, moveover, the reject loss through faulty control in the imperfect yarn windings has to be accepted into the bargain.
- Control and switching means for fluid driven traverse mechanisms in spinning, spooling and ring twist machines comprising a working cylinder having a piston reciprocal therein and a piston rod secured to the piston, switch means actuated by movement of said rod for controlling the speed and directional movement of said piston, control valve means responsive to said switch means for causing the piston to move toward one end of the cylinder or the other end thereof, fluid circuit means between said control valve means and said cylinder to control the speed of said piston including a fluid flow quantity regulator responsive to said switch means and connected in parallel with a fluid actuated controllable choke memher, and a fluid control means for controlling the opening and closing speed of said choke member.
- Control and switching means as defined in claim 1, wherein said fluid control means includes a control valve responsive to said switch means, and an auxiliary fluid flow quantity regulator.
- Control and switching means as defined in claim 2, wherein means is provided for electromagnetically operating said control valve means and said control valve in response to said switch means, and said quantity regulators is adjustable.
- Control and switching means as defined in claim 5, wherein said switch means includes a pair of stroke reversing switches operatively connected to said control valve means and a pair of control switches operatively connected to said control valve, and a switch actuator is carried on said rod.
- Control and switching means as defined in claim 4, wherein means is provided for adjustably mounting said stroke reversing and control switches to thereby adjust the piston movement.
- control and switching means for controlling the directional movement and speed of the piston rod
- said control and switching means comprising an electromagnetically operated main control valve for selectively connecting the opposite ends of the working cylinder to power and return to cause the piston rod to stroke toward each end of the cylinder, a pair of limit switches connected to said main control valve, a switch 8 actuator on said piston rod actuating said limit switches during movement thereof, fluid flow control means between said working cylinder and said main control valve regulating the fluid flow in the return cycle for each end of the cylinder including a fluid flow regulator parallel connected with a controllable variable choke member, an electromagnetically operated auxiliary control valve for controlling the operation of said choke member between open and closed positons, at least one control switch actuatable by said switch actuator and connected to said auxiliary control valve, and regulating means in the return of said auxiliary control valve for regulating the speed of
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Textile Engineering (AREA)
- Fluid-Pressure Circuits (AREA)
- Spinning Or Twisting Of Yarns (AREA)
- Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
Description
Jan. 16, 1968 c. RAMCKE 3,363,514
CONTROL AND SWITCHING DEVICE IN MECHANICALLY OR HYDRAULICALLY OPERATED TRAVERSE-MOTION SYSTEMS IN SPINNING, SPOOLING AND ESPECIALLY RING TWIST MACHINES Filed April 25. 1965 INVENTOR: CARSTEN R AM C K E mm wzg gw zoa aw MM;
ATT'YS United States Patent 7 Claims. 61. 91 24 The present invention relates to a control and switching device for hydraulically driven traverse mechanisms in spinning, spooling and, in particular, ring twist machines. More particularly, the subject invention relates to control and switching devices in which the directional change of the traverse stroke is caused by electrical end switches and wherein the movements of the working piston of the traverse drive temporarily undergo an acceleration as the amount of pressure fluid supplied to or led oii from the working cylinder per time unit is altered. In such control and switching mechanisms in hydraulically driven traverse systems it is a known practice to release the directional change of the traverse stroke by means of electric end switches or by setting members operating such switches which participate in the movement of the ring rail and/ or of the working piston of the hydraulic traverse system.
Further, it is a known practice in hydraulically driven traverse systems to fix the velocity of the traverse movement by means of adjustable quantity regulators arranged in the hydraulic line system. Finally, it has also been proposed that these quantity regulators to be fitted out adjus-tably and be shifted according to program over templates or cam pieces indirectly or directly actuated by the working piston or over levers or control rod systems.
Such mechanical shifting and control systems, however, take up -a relatively large space and present severe restrictions from a design standpoint. A further drawback lies in the fact that each time in the resetting of the traverse system for another winding form or type of distribution a change of the control mechanism is necessary, with its templates, cam pieces, and the like. Moreover, there lies a still more serious drawback in the fact that a relatively large number of cam parts and templates prepared according to empiricalyalues has to be on hand and that one is then bound to these special designs and cannot subsequently make whatever variations or corrections in the winding structure may be necessary.
The present invention, therefore, has as its basic objective the bringing about of speed changes of the stroke movement in hydraulically driven traverse systems hydraulically, but without such templates, cam parts or other mechanical control means and without the drawbacks inherent in these.
Other objects will become apparent to those skilled in the art from the following detailed description of the invention.
In general, the present invention is based on the insight that for a traverse stroke of constant velocity there is required for the moving of the working piston a certain amount of pressure fluid likewise remaining constant in the time unit, and that for the increase of the speed of the working piston there is necessary in each case a certain additional amount of pressure fluid per time unit, which, however, should be Variable within wide limits for the great variety of possible traverse programs. In order to achieve this it is proposed, according to the invention, to construct the control and switching device in such a way that in the feed and drain system of the hydraulic working circuit between the pump with its appropriate path valve on the one hand and the two Working cylinder sides on the other hand there is switched parallel to the adjustable quantity regulators allocated to each of these sides an additional feed and drain line each with a controllable choke member or a choke member in common. In this arrangement the choke member or members can be made controllable by means of a hydraulic dosing device, tor example,'a measuring pump, an auxiliary amount regulator, an auxiliary choke member, or the like, which is preferably arranged in the return flow of the hydraulic control circuit of the choke member. In this control circuit there can be provided, preferably, an electromagnetically operated control valve as, for example, a simple reversing slide.
Such an arrangement makes it possible for the adjusting of the basic speed necessary in each case of the traverse movement by means of quantity regulators arranged in known manner in the feed and/or drain line system of the working cylinder to use simple chokes, slide valves, and the like as quantity regulators. Moreover, the traverse speed can be altered at will by control of the flowthrough amount in the additional feed and/or drain lines engaged, according to the invention, parallel to the usual conduction system, by the method that the choke member provided in these lines, adjustable and possibly in common, is controlled, for example, in dependence on the working piston movement or according to a desired program. The choke member may be executed as control slide valve, quantity regulator, or the like. The control of the choke member takes place preferably over a hydraulic dosing device as well as an ordinary electromagnetic control valve which is operated by electric switching impulses in dependence on the time or, over limit switches, by the traverse program. For this purpose an especially driven impulse generator or else the already present electric limit switches which cause the direction change of the traverse stroke can be used, indirectly or directly. Likewise, however, one or several adjustable control switches may be allocated as impulse-givers for the choke member or choke members to the limit switches for the directional change of the traverse stroke, and this adjustable control switch or these adjustable control switches may be movable, if desired, directly or indirectly through the conveyor members which shift the limit switches for the directional change of the traverse stroke.
As compared to the known systems, there result several essential advantages. The throughput capacity of the choke member engaged, according to the invention, parallel to the quantity regulator is fully utilized for the control of the traverse speed. The control intensity is here considerably more sensitive and precise than in those quantity regulator systems in which only a fraction of the throughput is controlled. As another point, the hydraulic displacement of the choke member in a hydraulically driven traverse system does not present, say, only a constructively more expedient and less space-consuming solution, but actually brings about, in contrast to the known rigid mechanical control mechanisms, the realization of the demand to make it possible in a simple manner during the course of the program to make corrections and to carry out any variations that may subsequently still be necessary in the winding structure. It is precisely this, however, which is decisive in practical use. Even if the control and switching apparatus operates entirely automatically according to a program settable at will, it nevertheless frequently occurs, for example, after a change in the winding form or type of distribution or in the material: or denier, that it is necessary during running operation to modify the course of the program, and to make corrections which may possibly be necessary by hand. This is now possible in a simple manner with the aid of the device according to the invention.
In the drawing there is schematically represented an example of execution of the invention.
FIGURE 1 shows the electro-hydraulic control and switching system in a ring twist machine;
FIGURE 2 shows the modified arrangement of the electric control and limit switch; and
FIGURE 3 shows a form of the choke member in the hydraulic control system.
According to FIG. 1 the hydraulically driven traverse mechanism consists essentially of the ring rail 1, which is suspended on draw bands 2, which, in turn, are secured over deflection rollers 3 continuously with their other end on the piston rod 4 of the working piston 6, admitted on both sides, conducted in the hydraulic cylinder 5. On the piston rod 4 there is mounted the switching feeler 7, Which operates the limit switches 8, 9 for the release of the stroke reversal and also special control switches 10, 11 as impulse generators for the control of the traverse speed, in which arrangement the switches are shifted by the threaded spindles 12, 13, acting as conveying members, of, for example, electrically controlled program adjusting system 14. Such a program adjusting system is described in detail in application Ser. No. 374,109 which was filed on June 10, 1964, the disclosure of which is incorporated herein by reference.
The hydraulic working circuit of the traverse system consists of the pump 15 which conveys the pressure fluid from the supply tank 16 over the line 17 to the electromagnetically operated path valve 18. To the line 19 branching from line 17 there are connected a manometer 2i and a pressure limiting valve 21 for the measurement and setting of the pressure prevailing in the hydraulic system. According to FIG. 1, the switched-in zero position 22 of the path valve 18 is represented. The other switching positions are numbered 23 and 24. In the switching position 22 the pressure fluid conveyed by pump 15 flows through line 25 and back to supply tank 16. The lines 26-27 of the working circuit connect valve 18 with the two passages of adjustable choke member 28, which is represented in a special form of execution in FIG. 3 and is described in further detail below. From line 26 there branches the line 29 and leads over the permanently adjustable quantity regulator 30 or the nonreturn valve 31 engaged parallel to this and the line 32 to the left side of the working cylinder 5. The left-hand passage of the choke member 28 is connected through line 33 to line 32. Line 34 is connected to line 27 and leads over the permanently adjustable quantity regulator 35 or the nonreturn valve 36 arranged parallel to regulator 35 and the line 37 into the right-hand side of the working cylinder 5. Line 37 and the right-hand passage of the choke member 28 are connected with one another by line 38. From line 17 there branches off the control line 39 for the choke member 28 and leads into the valve 40 with its switching positions 41 and 42. From this: valve the control line 43 leads into the left-hand side of choke member 28, while the right-hand side of choke member 28 is connected through the control line 44 with the control valve 40. From valve 40 the control line leads over the dosing device 45, for example, a settable and adjustable auxiliary quantity regulator, back into supply tank 16.
In FIG. 2 there is shown a modified arrangement of the control and end switches. The limit switches 8 and 9 mounted on the spindles and conveyed through these carry sheet metal strips 46 and 47 with long holes 48 and 49, through which there are inserted screws 50 and 51, by means of which the control switches 10 and 11 are secured to sheet metal strips 46 and 47. In this manner the spacing between the limit switch 8 (or 9) and the control switch 10 (or 11) can be adjusted very easily and rapidly, while in the arrangement according to FIG. 1 it is first necessary to release a guide (not shown). and
then to screw the corresponding switch 10 or 11 by hand to the left or right.
FIG. 3, finally, shows the aforementioned choke member 28 in a special form. In the control cylinder casing 54 closed at the ends by means of covers 52 and 53, there is seated axially slidable the control piston, which consists essentially of three individual pistons 55, 56, 57 mounted at a distance from one another, which are solidly joined with one another by intermediate pieces 58, 59 of piston rod type. In covers 52 and 53 there are provided central bores 66, 61 for connection to the control lines 43, 44 (FIG. 1). The ring- shaped cylinder chambers 62, 63, 64, 65 each have a connecting bore 66, 6'7, 68, 69 leading through the cylinder casing wall for the pressure fluid lines, 26, 27, 33, 38 of the hydraulic working circuit. In each case there are made profiled grooves or notches 72, 73 in the right-hand annular end surface 70, 71 of the individual pistons 55, 56 which form the connecting channels between the paired annular cylindrical chamber 62/63 or 64/65.
The working positions represented in FIG. 1 of the individual hydraulic switching and control elements are only schematically shown and are not intended to characterize any particular situation in the course of a given working program. For the explanation of the functioning of the system there will here be described the build-up of one of the most usual types of thread or yarn windings. One is dealing here with a winding form with an approximately cylindrical middle portion and curved conical ends, the form and pitch of which is to be different. This winding form is caused by the fact that the relatively great traverse stroke of the ring rail, in relation to the total winding length, remains equal over the entire winding process and, from one end of the spool to the other, is slowly displaced during the entire winding process. In the process, the individual stroke has to be accelerated toward its ends. Means are provided for the formation of a thread reserve before the start of the winding process proper by means of individual or collective lowering of the spinning or twisting rings (not shown or described).
The threaded spindles 12 and 13 have thread rising to the right and turn, according to the winding program here selected as an example, at equal turning speed and like direction, so that the limit switches 8 and 9 and also the control switches 16 and 11 move from right to left with constant spacing, until one of them is operated by a blocking switch (not shown) for the termination of the winding program. During the process, the switch feeler 7 driven over piston rod 4, as described in detail further below, moves back and forth between limit switches 8 and 9.
After formation of the thread reserve the path valve 18 is automatically brought into its switching position 24 over the electrical control part. Pump 15 now conveys the drawn in pressure medium through lines 17, 18 (in switching position 24), 34, 36 and 37 into the right-hand side of the working cylinder 5. Now the working piston 6, with piston rod 4 and switching feeler 7, moves to the left which causes ring rail 1 to be raised by draw bands 2. After the first passage of the control switch 11 through switching feeler '7, the switches 9 and 11 become functionally active. In the movement of the working piston 6 to the left the pressure fluid released from the lefthand side of the working cylinder flows through lines 32, 30, 29 and 18 (switching position 24) as well as 25 back into supply tank 16. The amount of liquid flowing off, determined by the setting of the quantity regulator 30, determines the speed of working piston 6 andthereby also for that of ring rail 1.
Both passages 66, 62, 72, 63, 67 and 68, 64, 73, 65, 69 of adjustable choke member 28, in the parallel lines 26, 33, and 27, 38 to the quantity regulators 30 and are still closed at present. During its further movement to the left, switching feeler 7 actuates control switch 10 which, in turn, switches control valve 40 out of the switching position 41 into the switching position 42. Now pressure fluid passes through lines 39, 40 (switching position 42) and 44 through connection bore 61 into the right-hand chamber of choke member 28, both passages of which are opened hereby with uniform speed. The degree of opening speed of choke member 28 depends on the setting of the auxiliary quantity regulator 45, through which the pressure fluid emerging from connection bore 60 of the left-hand chamber of choke member 28 flows over line 43 and control valve 40 (switching position 42) back into supply tank 16. The greater the amount of fluid passing per time unit through auxiliary quantity regulator 45, the faster is the displacement of multiple piston 55, 56,
.57 of choke member 28 and the more rapidly, too, in-
creases the passage cross section 72, 73 of choke member 28 and with this also the amount of fluid flowing out per time unit from the left-hand side of working cylinder 5, under the pressure of the fluid flowing into its righthand side.
The speed of ring rail 1 increases toward the end of the traverse stroke proportionally to the amount of pressure fluid entering or leaving working cylinder 5, until switching feeler 7 actuates the stroke limiting switch 8, by which then the control valve 40 is switched back into switching position 41. Now, in the control line of choke member 28, the pressure fluid flows over lines 39, 40 (switching position 41) and 43 into connection bore 60 on the left-hand side of choke member 28. Correspondingly, the pressure fluid flows from its right-hand side over the control path 44, 40 (switching position 41), 45 back into supply tank 16. Choke member 28 is again closed according to setting of the auxiliary quantity regulator 45 at the same speed at which it was previously opened.
As a result of the operation of the limit switch 8 by switching feeler 7 the stroke reversal has been released, so that the following situation is created: The path valve 18 is switched into switching position 23, whereby the pressure fluid from pump now takes the following course into the left-hand side of working cylinder 5: line 17, valve 18 (switching position 23), lines 26 and 29, nonreturn valve 31 and line 3-2. The fluid emerging from the right-hand side of working cylinder 5 flows back over lines 37, 3 5, 34, 27, 18 (switching position 23) as well as into the supply tank 16. Simultaneously there flows parallel to it the fluid over line 38 branching off from line 37, the right- hand passage 68, 64, 73, 65, 69 of choke member 28 and lines 27, 18 (switching position 23), 25 into supply tank 16. Immediately after the stroke reversal by limit switch 8, therefore, the fluid can flow off over the permanently set quantity regulator and over choke member 28, the passage cross section of both of which together is thereby determinative for the speed of the pressure medium and of the working piston 6. The passage cross section of choke member 28 thereby becomes steadily smaller and, correspondingly, the amount of liquid flowing through the choke member is diminished. The speed of working piston 6 and ring rail 1 is thereby retarded until the passage of choke member 28 is completely closed and a uniform, relatively low piston speed is achieved, which is still determined only by the constant passage cross section of quantity regulator 35. This point is reached apparently when switching feeler 7 goes over control switch 10, the operation of which now, however, has no influence on any control element and, accordingly, has no influence on ring rail 1, since relay switches and relays have been switched on in the preceding cross of control switch 10, and they bring about the inactivation of the same until control switch 11 is pressed.
Now, after the closing of the choke member, the ring rail 1 descends, moving downward at a uniform rate. The working piston 6, with piston rod 4 and switching feeler 7, moves in the process to the right, until the latter reaches control switch 11 and actuates it. In the path valve 18 nothing is thereby altered. The stroke direction of working piston 6 continues to be maintained. But through the switching on of switch 11, the control valve 40 is brought from the switching position 41 back into the switching position 42, whereby the pressure fluid is passed through lines 17, 39, 40 (switching position 42) and 44 into the connection bore 61 of the right-hand side of choke member 28. This immediately begins to open again slowly, since from its left-hand chamber the pressure fluid there situated is pushed out through lines 43', 40 (switching position 42) and auxiliary quantity regulator 45 determining the degree of opening of the choke member and passes back into supply tank 1 6.
As a consequence of these control processes, as the passages become greater the amount of the fluid emerging from working cylinder 5 or of the fluid entering its other side increases per unit time. Working piston 6 moves on in each case from the moment of engagement of choke member 28 with constantly increasing speed and with it switching feeler 7. The latter soon strikes limit switch 8 or 9, which, in turn, by switching over path valve 18 from switching position 23 into switching position 24, or vice versa, causes the stroke reversal and simultaneously switches control valve 40' seated in the control line of choke member 28 from switching position 42 into switching position 41. In Working cylinder 5 the pressure fluid emerges from the one side, while the pres sure medium situated on its other side under pump pres sure has a driving effect on piston 6. For the control of adjustable choke member 28 the pressure fluid enters on its one piston side, while the liquid thrust out from the other chamber flows back over the adjusted auxiliary quantity regulator 45 into supply tank 16. The setting of auxiliary quantity regulator 45 determines the speed at which the passage cross sections of adjustable choke member 28 are opened and closed, and thereby the degree and the course of the acceleration and retardation of the movement of working piston 6 and ring rail 1. With the setting or adjustment of auixilary quantity regulator for differing throughput amounts of control fluid and with differing conformation of the passage slots in the multiple piston of the choke member, all conceivable acceleration and retardation relations can be achieved for the working piston movement. The carried-along switching feeler '7 runs over, in the back and forth passage, the control switches 10 and 11, and, namely, in each case immediately before the stroke reversal, for the purpose of the start of the acceleration, and immediately after the stroke reversal for the switching on of the functional readiness of the other control switch without further control function of its own.
As compared to the known control systems in which control cams or control plates are used, the proposed apparatus has the important advantage that any detectable deviations occuring during the winding process of the desired winding form can immediately be corrected by readjustment of auxiliary quantity regulator 45 and/ or of control switches 10 and 11. In contrast, the control cams or plates under these circumstances must be dismantled and interchanged in a complicated manner, or reworked or even completely remade and, moveover, the reject loss through faulty control in the imperfect yarn windings has to be accepted into the bargain.
Obviously many modifications and variations of the invention as hereinbefore set forth may be made Without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims. 1
I claim:
1. Control and switching means for fluid driven traverse mechanisms in spinning, spooling and ring twist machines comprising a working cylinder having a piston reciprocal therein and a piston rod secured to the piston, switch means actuated by movement of said rod for controlling the speed and directional movement of said piston, control valve means responsive to said switch means for causing the piston to move toward one end of the cylinder or the other end thereof, fluid circuit means between said control valve means and said cylinder to control the speed of said piston including a fluid flow quantity regulator responsive to said switch means and connected in parallel with a fluid actuated controllable choke memher, and a fluid control means for controlling the opening and closing speed of said choke member.
2. Control and switching means as defined in claim 1, wherein said fluid control means includes a control valve responsive to said switch means, and an auxiliary fluid flow quantity regulator.
3. Control and switching means as defined in claim 2, wherein means is provided for electromagnetically operating said control valve means and said control valve in response to said switch means, and said quantity regulators is adjustable.
4. Control and switching means as defined in claim 5, wherein said switch means includes a pair of stroke reversing switches operatively connected to said control valve means and a pair of control switches operatively connected to said control valve, and a switch actuator is carried on said rod.
5. Control and switching means as defined in claim 4, wherein means is provided for adjustably mounting said stroke reversing and control switches to thereby adjust the piston movement.
6. In a hydrualically driven traverse mechanism for spinning, spooling and ring twist machines having a working cylinder with a piston reciprocal therein and a piston rod secured to the piston, control and switching means for controlling the directional movement and speed of the piston rod, said control and switching means comprising an electromagnetically operated main control valve for selectively connecting the opposite ends of the working cylinder to power and return to cause the piston rod to stroke toward each end of the cylinder, a pair of limit switches connected to said main control valve, a switch 8 actuator on said piston rod actuating said limit switches during movement thereof, fluid flow control means between said working cylinder and said main control valve regulating the fluid flow in the return cycle for each end of the cylinder including a fluid flow regulator parallel connected with a controllable variable choke member, an electromagnetically operated auxiliary control valve for controlling the operation of said choke member between open and closed positons, at least one control switch actuatable by said switch actuator and connected to said auxiliary control valve, and regulating means in the return of said auxiliary control valve for regulating the speed of opening and closing of said choke member.
7. In a hydraulically driven traverse mechanism as defined in claim 6, wherein said choke member includes means for allowing greater fluid flow than said parallel fluid flow regulator when in open position.
References Cited UNITED STATES PATENTS 2,607,197 8/1952 Johnson 9l410 2,902,050 9/1959 Carls 91-24 3,191,505 6/1965 Defibaugh 91-40'7 2,962,001 11/1960 Morton et a1. 91398 3,222,997 12/1965 Blatter et al. 91407 FOREIGN PATENTS 585,819 10/1933 Germany.
OTHER REFERENCES Hydraulic Handbook, Editors of Hydraulic Pneumatic Power and Controls, Trade and Technical Press, England, T. J. 1963, pp. 44 and 355.
' MARTIN P. SCHWADRON, Primary Examiner.
P. T. COBRIN, B. L. ADAMS, Assistant Examiners.
UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,363,514 January 16, 1968 Carsten Ramcke It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:
Column 6, line 36, "auixilary" should read auxiliary Column 7 line 15 "is" should read are line 26 "hydrualically" should read hydraulically Column 8, line 26, "Blatter et a1." should read Blatt et al.
Signed and sealed this 25th day of November 1969.
(SEAL) Attest:
WILLIAM E. SCHUYLER, JR.
Commissioner of Patents Edward M. Fletcher, Jr.
Attesting Officer
Claims (1)
1. CONTROL AND SWITCHING MEANS FOR FLUID DRIVEN TRAVERSE MECHANISMS IN SPINNING, SPOOLING AND RING TWIST MACHINES COMPRISING A WORKING CYLINDER HAVING A PISTON RECIPROCAL THEREIN AND A PISTON ROD SECURED TO THE PISTON, SWITCH MEANS ACTUATED BY MOVEMENT OF SAID ROD FOR CONTROLLING THE SPEED AND DIRECTIONAL MOVEMENT OF SAID PISTON, CONTROL VALVE MEANS RESPONSIVE TO SAID SWITCH MEANS FOR CAUSING THE PISTON TO MOVE TOWARD ONE END OF THE CYLINDER OR THE OTHER END THEREOF, FLUID CIRCUIT MEANS BETWEEN SAID CONTROL VALVE MEANS AND SAID CYLINDER TO CONTROL THE SPEED OF SAID PISTON INCLUDING A FLUID FLOW QUANTITY REGU-
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEB76556A DE1203169B (en) | 1964-04-28 | 1964-04-28 | Control and switching device for hydraulically driven traversing devices in spinning, winding and especially ring twisting machines |
Publications (1)
Publication Number | Publication Date |
---|---|
US3363514A true US3363514A (en) | 1968-01-16 |
Family
ID=6979137
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US450467A Expired - Lifetime US3363514A (en) | 1964-04-28 | 1965-04-23 | Control and switching device in mechanically or hydraulically operated traverse-motion systems in spinning, spooling and especially ring twist machines |
Country Status (8)
Country | Link |
---|---|
US (1) | US3363514A (en) |
JP (1) | JPS4811289B1 (en) |
BE (1) | BE661436A (en) |
CH (1) | CH423572A (en) |
DE (1) | DE1203169B (en) |
ES (1) | ES311521A1 (en) |
GB (1) | GB1096859A (en) |
NL (1) | NL6504033A (en) |
Cited By (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3434283A (en) * | 1966-11-03 | 1969-03-25 | Simca Automobiles Sa | Hydraulic antishock device |
US3470692A (en) * | 1967-03-13 | 1969-10-07 | Int Harvester Co | Parallel dual accumulator seat suspension |
US3494258A (en) * | 1968-05-20 | 1970-02-10 | Ambac Ind | Solenoid operated valve control mechanism |
US3579740A (en) * | 1968-08-21 | 1971-05-25 | Husky Mfg Tool Works Ltd | Mechanism for closing and opening injection molds |
US3635020A (en) * | 1969-10-28 | 1972-01-18 | Zinser Textilmaschinen Gmbh | Driving system for moving rails of textile machines |
US3727600A (en) * | 1971-10-12 | 1973-04-17 | Park Tool Co | Hydraulic stone splitter with shock absorber means |
US3802318A (en) * | 1970-05-09 | 1974-04-09 | K Sibbald | Apparatus for controlling machines |
US3846049A (en) * | 1973-09-24 | 1974-11-05 | Oilgear Co | Intensifier pump with half wave modulator |
US3973747A (en) * | 1973-10-24 | 1976-08-10 | Atlas Copco Aktiebolag | Method of and arrangement for controlling the speed of the movements of hydraulic booms |
US4083291A (en) * | 1975-03-06 | 1978-04-11 | Volvo Bm Ab | Device for cross-cutting tree trunks |
US4412415A (en) * | 1980-02-21 | 1983-11-01 | Danfoss A/S | Hydrostatic steering gear |
US4504046A (en) * | 1983-05-10 | 1985-03-12 | Keitaro Yonezawa | Retracting clamp |
US4506871A (en) * | 1983-05-10 | 1985-03-26 | Aioi Seiki Kabushiki Kaisha | Retracting clamp |
US4548296A (en) * | 1980-02-26 | 1985-10-22 | Oil Drive Kogyo, Ltd. | Hydraulic elevator |
US4825745A (en) * | 1987-06-19 | 1989-05-02 | Bw Hydraulik Gmbh | Electrohydraulic control system |
US4877328A (en) * | 1988-04-12 | 1989-10-31 | Continental Aktiengesellschaft | Internal mixer |
US4889036A (en) * | 1987-05-30 | 1989-12-26 | Smc Corporation | Speed reducer for pneumatic actuator |
US4905933A (en) * | 1987-08-07 | 1990-03-06 | Teijin Seiki Company Limited | Control apparatus of control surface of aircraft |
US5325762A (en) * | 1992-10-29 | 1994-07-05 | Nordson Corporation | Fluid pressure operated piston engine assembly |
US5706713A (en) * | 1996-06-28 | 1998-01-13 | Kia Motors Corporation | Decelerating air pressure circuit for an air cylinder |
CN106043420A (en) * | 2015-04-08 | 2016-10-26 | 丹佛斯动力系统有限公司 | Hydraulic steering system |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1284339B (en) * | 1966-05-18 | 1968-11-28 | Zinser Textilmaschinen Gmbh | Hydraulic control device for controlling the speed of movement of benches on spinning, twisting or winding machines |
CH510577A (en) * | 1970-02-06 | 1971-07-31 | Buehler Ag Geb | Silo discharge device |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE585819C (en) * | 1931-07-22 | 1933-10-14 | Hauhinco Maschf | Carriage pusher |
US2607197A (en) * | 1949-08-06 | 1952-08-19 | Keller Tool Co | Sequential motor operation under control of individual, fluid actuated, relieved pressure valves |
US2902050A (en) * | 1956-11-06 | 1959-09-01 | Carls William | Control valve for fluid circuits |
US2962001A (en) * | 1958-11-07 | 1960-11-29 | Hartford Special Machinery Co | Hydro-pneumatic power mechanism |
US3191505A (en) * | 1961-11-21 | 1965-06-29 | William L Defibaugh | Hydraulic control for a slide unit |
US3222997A (en) * | 1963-05-27 | 1965-12-14 | Leland F Blatt | Pneumatic control system |
-
1964
- 1964-04-28 DE DEB76556A patent/DE1203169B/en active Pending
-
1965
- 1965-03-22 BE BE661436D patent/BE661436A/xx unknown
- 1965-03-30 NL NL6504033A patent/NL6504033A/xx unknown
- 1965-04-08 CH CH494565A patent/CH423572A/en unknown
- 1965-04-17 ES ES0311521A patent/ES311521A1/en not_active Expired
- 1965-04-23 US US450467A patent/US3363514A/en not_active Expired - Lifetime
- 1965-04-26 GB GB17492/65A patent/GB1096859A/en not_active Expired
- 1965-04-28 JP JP40024957A patent/JPS4811289B1/ja active Pending
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE585819C (en) * | 1931-07-22 | 1933-10-14 | Hauhinco Maschf | Carriage pusher |
US2607197A (en) * | 1949-08-06 | 1952-08-19 | Keller Tool Co | Sequential motor operation under control of individual, fluid actuated, relieved pressure valves |
US2902050A (en) * | 1956-11-06 | 1959-09-01 | Carls William | Control valve for fluid circuits |
US2962001A (en) * | 1958-11-07 | 1960-11-29 | Hartford Special Machinery Co | Hydro-pneumatic power mechanism |
US3191505A (en) * | 1961-11-21 | 1965-06-29 | William L Defibaugh | Hydraulic control for a slide unit |
US3222997A (en) * | 1963-05-27 | 1965-12-14 | Leland F Blatt | Pneumatic control system |
Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3434283A (en) * | 1966-11-03 | 1969-03-25 | Simca Automobiles Sa | Hydraulic antishock device |
US3470692A (en) * | 1967-03-13 | 1969-10-07 | Int Harvester Co | Parallel dual accumulator seat suspension |
US3494258A (en) * | 1968-05-20 | 1970-02-10 | Ambac Ind | Solenoid operated valve control mechanism |
US3579740A (en) * | 1968-08-21 | 1971-05-25 | Husky Mfg Tool Works Ltd | Mechanism for closing and opening injection molds |
US3635020A (en) * | 1969-10-28 | 1972-01-18 | Zinser Textilmaschinen Gmbh | Driving system for moving rails of textile machines |
US3802318A (en) * | 1970-05-09 | 1974-04-09 | K Sibbald | Apparatus for controlling machines |
US3727600A (en) * | 1971-10-12 | 1973-04-17 | Park Tool Co | Hydraulic stone splitter with shock absorber means |
US3846049A (en) * | 1973-09-24 | 1974-11-05 | Oilgear Co | Intensifier pump with half wave modulator |
US3973747A (en) * | 1973-10-24 | 1976-08-10 | Atlas Copco Aktiebolag | Method of and arrangement for controlling the speed of the movements of hydraulic booms |
US4083291A (en) * | 1975-03-06 | 1978-04-11 | Volvo Bm Ab | Device for cross-cutting tree trunks |
US4412415A (en) * | 1980-02-21 | 1983-11-01 | Danfoss A/S | Hydrostatic steering gear |
US4548296A (en) * | 1980-02-26 | 1985-10-22 | Oil Drive Kogyo, Ltd. | Hydraulic elevator |
US4504046A (en) * | 1983-05-10 | 1985-03-12 | Keitaro Yonezawa | Retracting clamp |
US4506871A (en) * | 1983-05-10 | 1985-03-26 | Aioi Seiki Kabushiki Kaisha | Retracting clamp |
US4889036A (en) * | 1987-05-30 | 1989-12-26 | Smc Corporation | Speed reducer for pneumatic actuator |
US4825745A (en) * | 1987-06-19 | 1989-05-02 | Bw Hydraulik Gmbh | Electrohydraulic control system |
US4905933A (en) * | 1987-08-07 | 1990-03-06 | Teijin Seiki Company Limited | Control apparatus of control surface of aircraft |
US4877328A (en) * | 1988-04-12 | 1989-10-31 | Continental Aktiengesellschaft | Internal mixer |
US5325762A (en) * | 1992-10-29 | 1994-07-05 | Nordson Corporation | Fluid pressure operated piston engine assembly |
US5706713A (en) * | 1996-06-28 | 1998-01-13 | Kia Motors Corporation | Decelerating air pressure circuit for an air cylinder |
CN106043420A (en) * | 2015-04-08 | 2016-10-26 | 丹佛斯动力系统有限公司 | Hydraulic steering system |
CN106043420B (en) * | 2015-04-08 | 2018-05-01 | 丹佛斯动力系统有限公司 | Hydraulic steering system |
US10161425B2 (en) | 2015-04-08 | 2018-12-25 | Danfoss Power Solutions Aps | Hydraulic steering system |
Also Published As
Publication number | Publication date |
---|---|
GB1096859A (en) | 1967-12-29 |
JPS4811289B1 (en) | 1973-04-12 |
NL6504033A (en) | 1965-10-29 |
ES311521A1 (en) | 1965-06-16 |
BE661436A (en) | 1965-07-16 |
DE1203169B (en) | 1965-10-14 |
CH423572A (en) | 1966-10-31 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3363514A (en) | Control and switching device in mechanically or hydraulically operated traverse-motion systems in spinning, spooling and especially ring twist machines | |
DE2514624C3 (en) | Control device for at least one hydraulically operated double-acting consumer | |
US2803110A (en) | Hydraulic power drive for reciprocating members | |
US4106710A (en) | Winding machines with contact roller control device | |
DE741521C (en) | Device for monitoring and maintaining a limited loop slack in elongated, flexible materials such as paper, rubber sheets and sheet metal | |
US4136600A (en) | Arrangement for controlling the speed of a hydraulic motor | |
US3269416A (en) | Control valve mechanism with means for reducing hydraulic shock | |
DE2249583A1 (en) | HYDRAULIC CONTROL VALVE SYSTEM | |
US2986124A (en) | Device for limiting the opening stroke of a tool-carrier | |
GB2205976A (en) | Electrohydraulic control system | |
US3381868A (en) | Drive for devices treating movable lengths of materials | |
CN1036730C (en) | Apparatus for controlling of hydraulic sliding valves | |
US3406918A (en) | Control and switching device in mechanically or hydraulically operated traverse-motion systems in spinning, spooling and especially ring twist machines | |
US3406919A (en) | Hydraulic means for controlling the movement of a ring or spindle rail | |
DE2713867C2 (en) | Device for closing the guide vanes of a hydraulic machine | |
CH337087A (en) | Device for automatically controlling the tool infeed on grinding machines, in particular internal grinding machines | |
US5135030A (en) | Electrohydraulic control system | |
DE3422978C2 (en) | Device for controlling a hydraulic actuating device | |
US3372544A (en) | Means for presetting and testing a desired pressure limit for hydraulically regulated refiner | |
DE2245017C3 (en) | Device for controlling the application of pressure medium to a working piston of an engine | |
US2320727A (en) | Hydraulic speed control apparatus | |
US3286941A (en) | Control device for programmed regulation of hydraulic fluid-operated traverse mechanisms of spooling, spinning and especially ring twist machines | |
US3379099A (en) | Installation for the automatic control of hydraulic jacks or like devices | |
DE10159403A1 (en) | Knitter, with a hydraulic drive for the guide needle bars, uses a hydraulic fluid where the viscosity can be varied by an electrical field set by electrodes from a controlled switching system | |
US3154923A (en) | Hydraulic drive for producing linear intermittent reciprocatory motions of a machine tool |