US3509501A - Time delay mechanism - Google Patents

Time delay mechanism Download PDF

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Publication number
US3509501A
US3509501A US670601A US3509501DA US3509501A US 3509501 A US3509501 A US 3509501A US 670601 A US670601 A US 670601A US 3509501D A US3509501D A US 3509501DA US 3509501 A US3509501 A US 3509501A
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Prior art keywords
time delay
relay
lever
case
delay device
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Expired - Lifetime
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US670601A
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English (en)
Inventor
Antonio Brovedan
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Pirelli and C SpA
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Pirelli SpA
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H43/00—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed
    • H01H43/24—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed with timing of actuation of contacts due to a non-rotatable moving part
    • H01H43/28—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed with timing of actuation of contacts due to a non-rotatable moving part the actuation being produced by a part, the speed of which is controlled by fluid-pressure means, e.g. by piston and cylinder
    • H01H43/285—Time or time-programme switches providing a choice of time-intervals for executing one or more switching actions and automatically terminating their operations after the programme is completed with timing of actuation of contacts due to a non-rotatable moving part the actuation being produced by a part, the speed of which is controlled by fluid-pressure means, e.g. by piston and cylinder adjusting the time interval by means of an adjustable orifice, e.g. needle valve

Definitions

  • Previously known time delay devices are generally cOnstructed with a chamber having a movable wall, such as a flexible diaphragm, a discharge valve, usually associated with the wall, and an inlet valve for regulating the rate of flow of the fluid into or out from the chamber.
  • the time delay action is initiated by actuating the movable wall inside the chamber with suitable control means.
  • the fluid inside the chamber is thereby evacuated via the discharge valve; and, by adjusting the rate of flow of fluid reentering the chamber, the speed of return of the movable wall, and of the controlling means associated therewith, to their original positions can be controlled.
  • Time delay devices of this type are often associated with control electromagnets and electric contacts.
  • the above describedpreviously known time delay devices are not well suited to size reduction.
  • the discharge valve is either inserted in a rigid central portion of the movable wall and is opened by the control means, or it is directly positioned in the very flexible diaphragm which constitutes the movable wall.
  • the first case considerable difliculties arise in machining miniature parts for such a valve, and other difficulties arise in providing an efficient control for the valve.
  • the second case i.e. when the valve is integral with the flexible diaphragm, it is diflicult to obtain complete evacuation of the chamber, and consequently operation of the devices is unsatisfactory.
  • time delay devices are often integrally associated with control electromagnets in a single unit; and in such case it becomes necessary to control the time delay device directly by the relay without, however, limiting the functional features of the relay. Also, the
  • time delay should be capable of being controlled either by energization or de-energization of the relay; and this capability should be achieved in a unit of minimum size.
  • energization delay will mean the delay obtained by energizing the magnet of the relay and the term de-energization delay will mean the delay obtained by de-energizing the relay.
  • the present invention makes possible the provision of a pneumatic time delay device of small size and devoid of the above mentioned difliculties of the prior art.
  • the time delay device of the present invention can be applied to an electromagnetic relay and integrated into a single unit. Moreover, it can be adjusted for delaying either the energization or the de-energization of the relay.
  • the time delay device of the present invention includes a housing provided with an internal cavity and a cover therefor.
  • the cover contains means for adjusting the rate of flow of fluid, i.e. air, therethrough.
  • a rigid movable element is arranged in the cavity, and is integral with the actuating means. The outer surface of the rigid element is configured to contact the inner surface of the cover.
  • a flexible annular diaphragm having thickened rims, is provided within the cavity. The central rim is housed in a suitable groove of the rigid element, and the peripheral rim is clamped between the cover and the base of the time delay device.
  • a first chamber is formed between the cover and the rigid element mounted on the flexible diaphragm.
  • a second chamber is also formed between the base and the opposite side of the element and flexible diaphragm.
  • a fluid duct extends out from within the first chamber; and means for regulating the rate of fluid flow are provided in this duct.
  • At least one opening is provided in the base and communicating out from the second chamber.
  • a valve is provided inside the rigid element for the passage of the fluid from the first to the second chamber. This valve is constituted by a valve seat formed by the inner surface of the rigid element and by a disc having on one side a peripheral sealing ring, and on the other side a central cylindrical protuberance onto which a spring is inserted. This spring acts between the rigid element and the disc to compress the latter against the seal about the sealing ring.
  • a compression spring is disposed in the cover of the time delay device and acts between the cover and the rigid element.
  • the rigid element is constituted by a hollow body whose inner and outer surfaces are in the form of superposed cylindrical steps having a diameter decreasing towards the cover of the time delay device.
  • the larger diameter end of the hollow body is closed by a cup integral with the means for controlling the time delay device.
  • This cup is provided with discharge openings and with a thickenetd rim encased in a groove obtained in the inner surface of the hollow body.
  • the seat for'the valve in the rigid element is constituted by a flat surface of an intermediate step inside the hollow body.
  • the means for controlling the time delay device are preferably constituted by a rigid shaft emerging from the base of the device.
  • the portion of the shaft outside the housing acts as a means for originating the displacement of movable electric contacts associated with the time delay device.
  • the electric contacts form a portion of an electric current breaking means.
  • Such means may comprise a microswitch associated with the time delay device.
  • the rigid shaft acts as a plunger to produce displacement of the contact bridge of the microswitch.
  • the switch is contained in a housing constituted by the base of the time delay device.
  • This housing may be provided at its outer periphery with a raised edge in order to form a recess, and by a base element having a corresponding recess so as to constitute, when the housing is joined to the base element, a closed cavity containing the current breaking means.
  • the base element is suitably bored to allow passage of the control shaft of the time delay device.
  • a kinematic device contained in an appropriate case connected to the base and to the housing of the relay.
  • This kinematic device is constituted by a first lever, one end of which is hinged in the case and the other end of which is provided with a pin; and by a second lever having a forkshaped end which embraces the pin of the first lever.
  • a compression spring is provided to impart to the first lever a force directed to keep the end of the carrier of the relay inside the housing. This spring is inserted at one end in a projection obtained in the first lever near the hinged end. The other end of the spring is provided with a flanged cap.
  • the case containing the kinematic device preferably has the same base perimeter as the relay to which it is applied; and, with respect to the latter, it can occupy only one position.
  • the wall of the kinematic case adjoining the base element is provided with an opening in which both ends of the second lever are positioned. This wall is also provided with a hole having a stop ledge.
  • the connection of the base element to the case containing the kinematic device is such that the end of the control shaft of said time delay device acts in thrust engagement with the fork-shaped end of the second lever of the kinematic device.
  • the end of the compression spring which is provided with the flanged cap is inserted in the opening of the wall of the case facing the base element so that the flange of the cap is in contact with the stop ledge of the hole.
  • the base element is connected to the case in a position rotated through 180 about the vertical axis of the time delay device.
  • the connection is such that the lateral opening in the wall of the case adjoining the base element is closed by this element; and the cap of the spring of the kinematic device presses against the base element through its opening and the end of the control shaft of the time delay device acts in thrust engagement with the end of the second lever of the kinematic device which is opposite to the fork-shaped end.
  • FIG. 1 is a side elevational view, taken in section, of a relay time delay device embodying the present invention as it appears at rest prior to delay operation when its relay electromagnet is energized;
  • FIG. 2 is a view similar to FIG. 1, showing the device in its reset position, with the electromagnet of the relay being de-energized;
  • FIG. 3 is a view similar to FIG. 1 but showing the device in its reset position and arranged to operate to delay relay de-energization with the relay electromagnet being de-energized;
  • FIG. 4 is an exploded perspective view showing the construction of a kinematic device used to operate the time delay device of FIGS. 1-3.
  • the time delay device of FIGS. 1-3 includes a cover 1 and a base 2, connected together by means of screws, (not shown).
  • the cover 1 and the base 2 are provided with facing recesses which in assembly, cooperate to form an inner closed cavity.
  • a rigid element 3 and a flexible diaphragm 4 divide this cavity into first and second chambers 5 and 6.
  • the first chamber 5 is the chamber to be evacuated while the second chamber 6 is the discharge chamber.
  • the rigid element includes a hollow body portion 7,: the inner and outer surfaces of which are shaped in the form of cylindrical steps whose diameter decreases towards the cover 1.
  • the cup 8 has a thickened rim 9, which is encased in a groove 10 in the cylindrical surface of the body 7.
  • Appropriate discharge holes 11 are formed around the bottom of the cup 8.
  • a control shaft 12 is formed integrally with and extends down from the center of the cup 8.
  • the flexible diaphragm 4 is of annular configuration and has thickened inner and outer edges 13 and 15.
  • the inner edge 13 is seated into a suitable groove 14 contained on the outer surface of the body 7 while the outer edge 15 is clamped between the base 2 and the cover 1 and is seated in a circular groove 16 contained in the latter.
  • the inner surface of the cover 1 is shaped in such a way as to mate with the outer surface of the rigid element 3.
  • a discharge valve for the evacuation of the chamber 5 is disposed inside the rigid element 3.
  • This discharge valve includes a seat formed by a step 17 of the inner surface of the hollow body 7 and by a disc 18, which is resiliently biased against the step 17.
  • a suitable annular sealing ridge 19 formed on the disc 18 presses against the step 17 to effect sealing.
  • a spring 20 is provided to maintain the necessary resilient bias. One end of the spring 20 is inserted on a cylindrical central protuberance 21 of the disc 18 and the other end of the spring presses against the cup 8.
  • a wall return spring 22 is inserted at one end in the seat 23 of the cover 1 of the time delay device; and is disposed at its other end about the cylindrical surface of the rigid element 3.
  • the wall return spring pushes the rigid element 3, together with its associated control shaft 12, downwardly towards the outside of the housing of the time delay device.
  • the control shaft 12 emerges downwardly from the base 2 through a hole 24.
  • One or more additional openings 25 are formed in the base 2 to permit discharge of fluid to the outside.
  • a pin valve 26 is inserted in the cover 1. This valve, at its outer end, carries a knurled wheel 27 and a guide 28.
  • the guide 28 may be calibrated to act as an index.
  • a pin 29 At the other end of the valve 26 there is provided a pin 29.
  • the central threaded portion of the pin valve 26 is screwed in a hole 30 contained in the cover 1.
  • the valve is turned by the wheel 27 and pushes the pin 29 against a duct 31 which serves as a valve seat. In this way the opening of the valve, and therefore the obtainable time delay, can be controlled.
  • a filter 32 Upstream of the duct 31 and the pin 29, there is provided a filter 32 which is suitably protected by a grid 33.
  • a passage 34 Downstream of the duct 31 there is provided a passage 34, which connects the duct to the chamber 5.
  • the base 2 of the time delay device is formed outwardly with respect to the chamber 6, with a second recess which mates with a corresponding recess contained in an appropriate base element 35.
  • the base 2 and base element 35 are held together by means of screws which may be similar to those used for fastening the cover 1 to the base 2.
  • a cavity 36 is thus formed between the base 2 and the base element 35.
  • This cavity contains a microswitch which is constiuted by the pairs of stationary contacts 37a and 37b, 38a and 38b, and by the movable contacts 39 carried by a bridge 40.
  • the bridge 40 is slidably inserted in the lower part of the shaft 12 which emerges from the base 2.
  • a fulcrum 41 formed by two wedgeshaped indentations 41a and 41b, is contained in this lower part of the shaft.
  • the shaft 12 emerges from the base element 35 as a plunger 43 which is actuated by an appropriate kinematic device disposed between it and an upwardly protruding end 44 of a carrier 68 of an associated electromagnetic relay 70.
  • the relay 70 includes a housing 72 which is connected to the timing device. The carrier 68 moves up and down within the housing 72. A return spring 74 biases the carrier 68 toward and upward position while a relay coil 76 surrounding the coil serves magnetically to force the coil down in the position shown in FIG. 1 when the relay is energized.
  • the kinematic device is conta ned in a case 45, joined at one side to the base element 35, and therefore to the housing of the time delay device.
  • the case 45 is held on one side to the base element 35 by means of screws (not illustrated), and on the other side it is held to an electromagnetic relay with which it is to be associated, by connecting means not forming part of the present invention.
  • the case 45, the base element 35, the base 2, and the cover 1, as thus joined together, constitute a single unit which is directly applicable to an electromagnetic relay.
  • the case 45 is provided with an opening 46 for the passage of the plunger 43. It is also provided with a hole 47 which may correspond to a recess 48, in the element 35. The function of these items will be explained hereinafter.
  • the kinematic device contained in the case 45 is constituted by a first lever 49 which is hinged at one end 50 in the case, and is pivotally interconnected at its other end 51 with another lever 52.
  • the other lever 52 is also hinged in the case 45 at an intermediate location 53.
  • the lever 49 is constituted by two lateral straps 49a and 49b. These straps are connected by three ties 54, 55 and 56.
  • the tie 54 contains pins 54a and 54b by means of which the lever engages in the case 45.
  • a boss 57 for receiving helical compression spring 58 is also provided on the tie 54.
  • the tie 55 is of triangular section and constitutes the support for the lever 49 on the carrier 44.
  • the tie 56 is of circular section and serves as a pin for interconnection with a fork-shaped end 59 of the lever 52.
  • the lever 52 is constituted by a single piece and is directly pivoted in the case 45.
  • the ends 59 and 60 of the lever 52 have cam-shaped profiles which interact with the plunger 43 of the microswitch. This one of these two ends is in position directly beneath the opening 46 of the case.
  • the end of the spring the lever 49 is provided 62.
  • the spring and cap hole 47 in the recess 48 58 which is not engaged in with a cap 61 having a flange together penetrate through the of the base element 35. If the time delay device is to be operated to delay the de-energization of the relay, it is assembled on the case 45 in a position in which the hole 47 of the case corresponds to the recesses 48 of the base element 35. On the other hand if the device is to be operated to delay the energization of the relay, it is assembled on the case 45 in a position rotated about an axis AA from its first position. 'In such position the opening 46 is closed by the base element 35.
  • the spring 58 In the first position of the device the spring 58 extends into the recess 48 until the flange 62 on the cap 61 becomes stopped by the edge of the hole 47. In the second position of the device the hole 47 is moved away from the spring 58 and the bottom of the base element 35 holds the spring under compression.
  • FIGURE 1 shows the time delay device in rest posi tion.
  • the plunger 43 is pressed upwardly. This serves to push the rigid element 3 up inside the chamber 5 and at the same time displaces the bridge 40 from the position in which it connects the contacts 37a and 37b to the position in which it connects the contacts 38a and 38b.
  • the evacuation of the chamber 5 is, moreover, complete, because its entire volume is displaced by the rigid element 3 as its outer surface mates with the inner surface of the cover 1.
  • the wall return spring 22 pushes the rigid element 3 back towards its rest position. This creates in the chamber 5 a pressure reduction relative to the chamber 6 and to the outside.
  • the resultmg external overpressure opposes the movement of the rigid element 3 towards its rest position.
  • it allows the admission of external air or other fluid to the chamber 5 through the pin valve 26.
  • This admission of fluid lessens the pressure reduction in the chamber 5 and permits a gradual return of the rigid element 3 to its rest position.
  • the rate at which this return takes place can be controlled by adjusting the degree of insertion of the pin 29 into the duct 31. As a result the bridge 40 will reclose the contacts 37a and 37b, after a predetermined duration following their opening.
  • the time delay device of the present invention can be operated to effect delay upon both the de-energization and the energization of the electromagnet of a relay.
  • the kinematic device which permits it to be reset in either of these conditions. This is achieved by rotatively shifting its position with respect to the case 45.
  • the time delay device is assembled on the case 45 in such a way as to initiate delay upon the energization of the relay electromagnet; and as shown the device is in rest position.
  • the rest position of the time delay device corresponds to the condition in which the electromagnet of the relay is energized; and therefore the end 44 of the carrier of the relay is disposed inside the housing 72.
  • the kinematic device is in its normal position with the spring 58 maintaining the lever 49 in horizontal position, while the lever 49, in turn, keeps the end 59 of the lever 52 down from the plunger 43.
  • the spring 58 is at this point in a condition of maximum extension since its end provided with the cap projects into the recess 48 of the base element 35. Therefore the resistance it imparts to the lever 49 is minimum. Moreover, as the point at which the spring 58 acts is very near to the hinge 50, its action does not greatly affect the return spring 74 of the carrier. This is advantageous, because the return spring 74 of the carrier has also to overcome the reaction of the spring 22 of the time delay device to bring it to the position shown in FIG. 2.
  • the time delay device is shown in FIG. 3 in its reset position, with the electromagnet coil 76 of the relay 70 energized and the end 44 of the carrier 68 inside the relay housing 72.
  • the spring 58 remains inside the case 45 because the hole 47 is closed by the bottom of the base element 35. Moreover, since the spring 58 is compressed, it can provide a force suflicient to keep the lever 49 in a horizontal position. The lever 49 in turn causes the end 60 of the lever 52 to be lifted, in opposition the reaction exerted by the wall return spring 22 via the plunger 43.
  • the return spring 74 of the carrier 68 only has to oppose the action of the spring 58; and, even if the latter is compressed, the resistance which the return spring 74 may impart to the lever 49 is not greater than the resistance imparted by it, together with the spring 22 of the time delay device, in the preceding case of delay to energization.
  • a time delay device comprising: a housing formed with an internal cavity; means inside the cavity for regulating the rate of fluid flow between the cavity and the outside of said housing; a movable wall including a rigid movable element arranged in said cavity; actuating means for applying pressure to said rigid movable element for moving said wall; said movable wall further surrounding and sealably secured to the rigid element and extending across said cavity; said wall dividing the cavity into a first chamber containing the means for regulating the rate of fluid flow, and a second chamber, a fluid duct connecting the outside with the first chamber through the means for regulating the rate of fluid flow; said second chamber being in open fluid communication to the outside; a valve mounted within the rigid element for permitting the passage of fluid from the first to the second chamber, said valve including a valve seat formed on an inner peripheral surface of said rigid element and a movable valve element having on one side a peripheral sealing surface and on the other side means for receiving a bias force against said valve seat, a bias spring acting between the rigid element and the valve element to force the
  • a time delay device as in claim 1 wherein the rigid element comprises a hollow body having inner and outer surfaces in the form of superimposed cylindrical steps, the larger diameter end of the hollow body being covered by a cup provided with discharge openings, and to which is attached said actuating means and the valve seat inside the rigid element being constituted by the flat surface of an intermediate step inside the hollow body.
  • a time delay device as in claim 3 wherein a relay may be associated with the time delay device, said device including a kinematic device interposed between the end of the rigid shaft emerging from the housing of the device and the end of a contact carrier projecting from the housing of an associated relay, said kinematic device being contained in an appropriate case connected between said time delay device and such relay, said kinematic device including a first lever hinged in said case and a second lever also hinged in said case and arranged to be acted upon by the first lever, the first lever being arranged to be acted upon by the carrier of a relay and the second lever being arranged to act upon said rigid shaft, a compression spring mounted to impart to the first lever a force against such carrier, said case having in its wall adjoining said housing an opening exposing both ends of the second lever and a hole through which said compression spring protrudes, said housing having a bottom wall and a recess and being mountable on said case in different positions selectively bringing said opening and said hole intoregistry with said compression spring.
  • a device as in claim 5 wherein said housing is connected to said case and is disposed thereon in a position on an associated relay such that the end of said rigid shaft acts in thrust engagement with the end of the second lever of the kinematic device which moves the first lever in the same direction, the protruding end of the compression spring being provided with a cap inserted in said hole in said case adjoining said housing, and said cap having a flange in contact with the edge of said hole, and said relay being arranged to move its carrier down from said time delay device upon energization, said time delay device being thus operative to delay the energization of said relay.
  • a device as in claim -5 wherein said housing is connected to said case and is disposed thereon in a stationary position on an associated relay such that said hole formed in the wall of the case adjoining said housing is closed by the latter, and the protruding end of said compression spring of the kinematic device presses against said housing through said hole, the end of said rigid shaft acting in thrust engagement with the end of the second lever of the kinematic device which moves in opposite direction to said first lever, and said relay being arranged to move its carrier down from said time delay device upon energization, said time delay device being thus operative to delay the de-energization of said relay.
  • a time delay device comprising a housing, an actuating member mounted on and movable with respect to said housing, means in said housing permitting rapid movement of said actuating member in one direction and slower movement of said actuating member in the other direction, a casing configured to be mounted on said housing in either of two positions, a pivotally mounted lever contained within said casing and having actuating References Cited UNITED STATES PATENTS 3,249,716 5/1966 Haydu 335-61 BERNARD A. GILHEANY, Primary Examiner H. BROOME, Assistant Examiner US. Cl. X.R. 200-166

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US670601A 1966-10-17 1967-09-26 Time delay mechanism Expired - Lifetime US3509501A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IT2891866 1966-10-17

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US3509501A true US3509501A (en) 1970-04-28

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Application Number Title Priority Date Filing Date
US670601A Expired - Lifetime US3509501A (en) 1966-10-17 1967-09-26 Time delay mechanism

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US (1) US3509501A (xx)
BE (1) BE705003A (xx)
CH (1) CH483714A (xx)
DK (1) DK126608B (xx)
ES (1) ES346098A1 (xx)
GB (1) GB1202395A (xx)
LU (1) LU54677A1 (xx)
NL (1) NL6713742A (xx)
NO (1) NO121682B (xx)
SE (1) SE342352B (xx)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3671891A (en) * 1970-08-31 1972-06-20 Matsushita Electric Works Ltd Small type electromagnetic contactor
US3775710A (en) * 1971-08-06 1973-11-27 Square D Co Pneumatic timer attachment for an electromagnetic relay
US4038619A (en) * 1975-10-01 1977-07-26 Cutler-Hammer, Inc. Pneumatic timer
US4315231A (en) * 1979-12-10 1982-02-09 Hitachi, Limited High-speed circuit breaker
US4535310A (en) * 1983-09-02 1985-08-13 Square D Company Pneumatic timing attachment for an electromagnetic device
CN109695656A (zh) * 2019-01-25 2019-04-30 科马智能悬架技术(苏州)有限公司 一种零负阻尼磁流变减振器
CN110718417A (zh) * 2019-10-30 2020-01-21 苏州辰晟优机电科技有限公司 继电器

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0273036U (xx) * 1988-11-24 1990-06-04

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3249716A (en) * 1963-12-26 1966-05-03 Allen Bradley Co Time delay device

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3249716A (en) * 1963-12-26 1966-05-03 Allen Bradley Co Time delay device

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3671891A (en) * 1970-08-31 1972-06-20 Matsushita Electric Works Ltd Small type electromagnetic contactor
US3775710A (en) * 1971-08-06 1973-11-27 Square D Co Pneumatic timer attachment for an electromagnetic relay
US4038619A (en) * 1975-10-01 1977-07-26 Cutler-Hammer, Inc. Pneumatic timer
US4315231A (en) * 1979-12-10 1982-02-09 Hitachi, Limited High-speed circuit breaker
US4535310A (en) * 1983-09-02 1985-08-13 Square D Company Pneumatic timing attachment for an electromagnetic device
CN109695656A (zh) * 2019-01-25 2019-04-30 科马智能悬架技术(苏州)有限公司 一种零负阻尼磁流变减振器
CN110718417A (zh) * 2019-10-30 2020-01-21 苏州辰晟优机电科技有限公司 继电器

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Publication number Publication date
ES346098A1 (es) 1968-12-01
SE342352B (xx) 1972-01-31
GB1202395A (en) 1970-08-19
DK126608B (da) 1973-07-30
DE1650502B2 (de) 1976-03-18
BE705003A (xx) 1968-02-15
NO121682B (xx) 1971-03-29
CH483714A (it) 1969-12-31
NL6713742A (xx) 1968-04-18
LU54677A1 (xx) 1967-12-18
DE1650502A1 (de) 1970-10-22

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