FR2997546A1 - Linear electromagnetic actuator for controlling opening and closing of e.g. motor vehicle's exhaust gas recirculation valve, has air-gap area provided between cylinder head and moving part and located outside internal volume defined by coil - Google Patents

Abstract

The actuator (1) has a cylinder head (5) used as a support to a coil (3) connected to an electrical supply unit. A moving part (9) is guided in translation in a housing (7) of the head. A spring (15) is arranged to position the part in a stable rest position in absence of power supply of the coil. The coil causes translational displacement of the part toward a stable position under effect of magnetic flux created by the supply. An air-gap area is provided between the head and the part, and is constant on variable opposite surfaces and located outside an internal volume defined by the coil.

Description

The present invention relates to the field of linear actuators and in particular linear electromagnetic actuators used in motor vehicles.

In the state of the art, different types of electromagnetic actuators are used for motor vehicle engine applications. Different actuator technologies are used depending on the applications and in particular as a function of the travel required for the actuator between its rest position and its closed position, that is to say its position where the movable part comes into contact with the cylinder head. and close the gap. Indeed, for low stroke distances, as for example in the injectors, it is mainly used variable air gaps that provide a large actuating force over a short distance. For longer stroke distances, mainly constant air gaps and variable facing surfaces are used which allow travel over greater distances but require more energy than variable air gaps to keep the actuator in the closed position. Thus, for strokes of more than 0.5 mm, the electromagnetic actuators of the state of the art require a relatively high energy to perform the actuation. The object of the present invention is therefore to propose a solution making it possible to optimize the efficiency of an actuator having a stroke greater than 0.5 mm while minimizing the energy required for its actuation. The embodiments of the present invention therefore relate to a linear electromagnetic actuator comprising: a yoke which serves to support a coil, said coil being configured to be connected to electrical supply means, a guided mobile part in translation in a housing of the cylinder head, said housing being located at least partially in an internal volume defined by the inside of the coil and extending along the longitudinal axis of the coil, - an elastic means configured to position the part movable in a first stable position of rest in the absence of supply of the coil, BRT 1056 (CFR0573) -2- the coil being configured to cause the displacement in translation of the movable part to a second stable position under the effect of a magnetic flux created by the supply of the coil, the actuator comprising at least one gap zone between the yoke and the moving part, in the at least one gap zone is a constant air gap zone with variable facing surfaces and is located outside the internal volume defined by the inside of the coil. According to another aspect of the present invention, the constant air gap area with variable facing surfaces is defined by two surfaces respectively belonging to the yoke and the moving part, such that, when the moving part is moved from the first to the second position, the area of their portions opposite varies and the distance separating said surfaces remains constant. According to a further aspect of the present invention, the yoke comprises a cavity extending along the axis of the coil and outside the internal volume defined by the inside of the coil, and an end of the moving part is configured to protrude into said cavity during its displacement in translation to the second stable position, the peripheral surface of the movable part and the lateral surface of the cavity forming a constant air gap zone with variable facing surfaces.

According to an additional aspect of the present invention, the movable portion has a first portion having a cross section greater than that of a second portion, and the yoke comprises a shoulder configured to be vis-à-vis the first portion during the first portion. displacement in translation of the movable portion to the second stable position, the surfaces of said first portion and the shoulder which are opposite forming a constant air gap area with variable viewing surfaces. According to another aspect of the present invention, the shoulder is at the part of the breech defining the entrance of the housing.

According to a further aspect of the present invention, the second portion is defined by a radial recess of the movable portion and / or the first portion is defined by a radial over-thickness of the movable portion. According to an additional aspect of the present invention, the movable portion extends out of the breech housing and the outer portion to the breech includes a radial protrusion which extends beyond the breech. area defined by the entrance of the dwelling.

According to another aspect of the present invention, the yoke comprises an inner wall which extends at least partially in the internal volume defined inside the coil so as to define the housing. According to a further aspect of the present invention, the yoke comprises an outer wall which surrounds an outer wall of the coil, said outer wall comprising a leg extending towards the inner wall; an opening is provided between the inner wall and said branch; and the radial protuberance of the movable portion comprises a protuberance which is configured to protrude into said opening during translational movement of the movable portion to the second stable position, the lateral surfaces of the protuberance and the inner surface of the movable portion. opening which are opposite forming a zone with constant air gap and variable facing surfaces. According to another aspect of the present invention, the actuator also comprises at least one variable gap zone. According to a further aspect of the present invention, the zone with variable air gap is defined by two facing surfaces respectively belonging to the movable part and the cylinder head, such that, when the moving part is moved from the first to the second position, the distance separating said surfaces varies and the area of their opposite portions remains constant. According to an additional aspect of the present invention, the at least one variable gap zone is located outside the internal volume defined by the inside of the coil. According to another aspect of the present invention, said radial outgrowth is configured to form a variable gap area with the surface of the peripheral yoke at the entrance of the housing. Embodiments of the present invention also relate to a motor valve disconnect device comprising an actuator which is configured to allow or not actuation of the valve by a cam. Embodiments of the present invention also relate to a solenoid valve comprising an actuator which is configured to control the opening and closing of the solenoid valve.

Embodiments of the present invention also relate to an exhaust gas recirculation valve including an actuator that is configured to control the opening and closing of the valve.

Other features and advantages of the invention will appear in the description which will now be made, with reference to the accompanying drawings which show, by way of indication but not limitation, possible embodiments. In these drawings: FIG. 1 represents a sectional view of a linear actuator according to a first embodiment; - Figure 2 shows a sectional view of a linear actuator according to a second embodiment; - Figure 3 shows a sectional view of a linear actuator according to a third embodiment; - Figure 4 shows a sectional view of a linear actuator according to a fourth embodiment; FIG. 5 shows a sectional view of a linear actuator according to a fifth embodiment; - Figure 6 shows a sectional view of a linear actuator according to a sixth embodiment; - Figure 7 shows a sectional view of a linear actuator according to a seventh embodiment; Figure 8 shows a perspective view of a canister valve; FIG. 9 represents a sectional view of the internal device of a canister valve according to the invention; In these figures, the same reference numbers designate identical elements.

In the description which follows, generally refers to: The term "cylinder head" corresponds to the portion surrounding the coil and used to concentrate the magnetic flux created by the coil and is translated by the term "yoke" in English.

The term "air gap or gap zone" corresponds to an area in which the movable portion and the yoke are close to each other so that a magnetic flux can pass from one to the other. The term "variable gap" defines an airgap zone in which movement of the movable portion under the effect of the magnetic flux tends to alter the distance between the surfaces of the movable portion and the yoke. The term "constant air gap with variable facing surfaces" corresponds to an air gap zone in which the displacement of the moving part under the effect of the magnetic flux tends to modify the surface of the moving part which is opposite the surface of the cylinder head, the distance between the two surfaces remaining substantially identical in this area. Embodiments of the present invention relate to a linear electromagnetic actuator comprising at least one constant gap zone and variable viewing surfaces. The zone with constant air gap and variable facing surfaces is located outside the internal volume defined by the inside of the coil. This makes it possible to maximize the diameter of the mobile part situated in this internal volume and thus to optimize the magnetic flux flowing inside this internal volume. This results in a reduction of the energy required for the operation of the actuator. FIG. 1 shows a first embodiment of a linear electromagnetic actuator BRT 1056 (CFR0573) 1. The actuator 1 comprises a spool 3, preferably wound on a support 4. The spool 3, if appropriate the assembly formed of the support 4 and the coil 3, is supported by a yoke 5 which surrounds the coil 3. The yoke 5 comprises in particular an outer wall 50 which surrounds the outer wall of the coil 3. The support 4 is a support mechanical, magnetically inert, for example in the form of a plastic overmoulding. The yoke 5, generally made of ferromagnetic material, makes it possible to circulate the magnetic flux created by the coil 3 when the latter is energized. The coil 3 is preferably in the form of a cylinder. However, the coil 3 may also have other tubular shapes. The coil 3 is configured to be electrically powered, for example by being connected to power supply means. The yoke 5 comprises a housing 7 which occupies at least partially the internal volume defined by the inside of the coil 3. The axis of the housing 7 coincides with the axis of the coil 3 so that the housing extends according to the longitudinal axis of the coil 3. In this example, the inner surface of the support 4 of the coil 3 partially defines the wall of the housing 7. The housing 7 extends beyond the internal volume defined by the interior of the the coil to form a cavity 8 in the cylinder head 5. The actuator 1 also comprises a movable part 9 guided in translation in the housing 7 of the cylinder head 5. The translational guidance can be achieved by the walls of the housing 7 and / or by the presence of a guide 11 located in the axis and in the center of the housing 7. The guide 11 is secured to the yoke 5 and is inserted into a central hole 13 of the movable part 9. The diameter of the guide 11 and the central orifice 13 are relatively small compared to the diameter of the p mobile part 9 to limit the loss of magnetic flux inside the internal volume defined by the inside of the coil 3. Preferably, the guide 11 is a non-magnetic material to avoid parasitic magnetic flux created by the coil L the actuator 1 also comprises an elastic means 15, for example a spring, configured to position the mobile part 9 in a first stable rest position when there is no magnetic flux created by the coil 3, that is, that is, when the coil 3 is not electrically powered. The elastic means 15 opposes the displacement of the movable portion 9 under the effect of the magnetic flux created by the coil 3 when the latter is electrically powered. The spring 15 is for example arranged around the guide 11 and is supported by a BRT 1056 (CFR0573) -7- part on the bottom 16 of the housing 7 of the yoke 5 and secondly on a shoulder 17 of the moving part 9. The actuator 1 has at the cavity 8, a variable air gap between the inner surface of the yoke 5 defining the bottom 16 of the housing 7 and the end 19 of the movable part 9 facing said bottom 16 At the level of the variable gap, during the translational movement of the movable part 9, the distance separating the facing surfaces varies and the area of their opposite portion remains constant. The actuator 1 has, always at the level of the cavity 8, a constant air gap with variable facing surfaces between the lateral surface 18 of the cavity 8 and the peripheral surface 20 of the mobile part 9 situated opposite the lateral surface 18 of the cavity 8 when the movable portion 9 protrudes into said cavity 8. During the displacement in translation of the movable part 9 towards the bottom 16 of the housing 7, the peripheral surface 20 of the movable part 9 facing the lateral surface 18 of the yoke 5 varies in being larger and larger and creates a constant air gap zone with variable facing surfaces in which the area of the opposite portions varies while the distance separating said surfaces remains constant. These gap zones are located outside the internal volume defined by the inside of the coil 3 so that the magnetic flux flowing in this internal volume is maximized. The moving part 9 of the actuator 1 is thus displaced in translation towards the bottom 16 of the housing 7 under the effect of the magnetic fux transmitted at the gap zones, said magnetic flux being created by the coil 3 when the latter is powered. Figure 2 shows a second embodiment. This second embodiment differs from the first embodiment in that the mobile part 9 comprises a radial protrusion 21, at its part extending axially outside the housing 7.

The radial protrusion 21 extends beyond the surface defined by the inlet of the housing 7 and faces the outer surface 22 of the yoke 5 located at the periphery of the inlet of the housing 7. The radial protuberance 21 may be integral with the rest of the movable portion 9 or assembled to the movable portion 9 by fixing means. Thus, the surface 24 of the radial protuberance 21 facing the outer surface 22 of the yoke 5 and the surface of the yoke 5 peripheral to the inlet of the housing 7 form a variable gap area. This variable air gap zone BRT 1056 (CFR0573) -8- is also external to the internal volume defined by the inside of the coil 3 and makes it possible to further improve the efficiency of the actuator 1 with respect to the first embodiment. . Fig. 3 shows a third embodiment. This third embodiment differs from the second embodiment in that the movable portion 9 has a first portion having a cross section greater than that of a second portion and a shoulder 26 configured to be opposite the first portion. portion during displacement in translation of the movable portion 9 to the second stable position. In the embodiment of Figure 3, the second portion is formed by a radial recess 23. The shoulder is formed by the inner surface 26 of the yoke 5 defining the inlet of the housing 7. When the movable part 5 is in the first stable rest position, the radial recess is opposite the surface 26 of the yoke 5 defining the inlet of the housing 7. During the translational movement of the movable part 9 towards the bottom 16 of the housing 7, the surface external side 28 of the movable portion 9 located between the radial protrusion 21 and the recess 23 comes opposite the inner surface 26 of the yoke 5 defining the entrance of the housing 7. These two surfaces 26, 28 create a zone of constant air gap with variable surfaces. This gap zone is external to the internal volume defined by the inside of the coil 3 and therefore optimizes the magnetic flux flowing in this internal volume. Moreover, it should be noted that it is possible to have a lateral recess 23 without having radial protuberance 21 or cavity 8. The effects of the different gap zones thus created are complementary. Figure 4 shows a fourth embodiment. This fourth embodiment differs from the third embodiment in that the first portion is formed by a radial over-thickness 27 complementary to the shoulder 26 of the yoke 5. Thus, during the translational movement of the moving part 9 towards the bottom 16 of the housing 7, the lateral outer surface 28 of the movable portion 9 at the radial over-thickness 27 comes opposite the inner surface 26 of the yoke 5 defining the inlet of the housing 7. These two surfaces 26 , 28 create a constant gap zone with variable viewing surfaces. This air gap zone is external to the internal volume defined inside the coil 3.

The example of FIG. 4 appears as an alternative to that of FIG. 3. These two examples also have two zones of variable air gap and two constant air gap zones with variable viewing surfaces. all of these gap zones being located outside the internal volume defined inside the coil 3. It should be noted that in the third and fourth embodiments, the presence of the radial protrusion 21 and or cavity 8 is optional. FIG. 5 represents an exemplary actuator according to a fifth embodiment. This embodiment differs from the previous embodiments in that the yoke 5 comprises an inner central portion or inner wall 30 on which the coil 3 is wound.

This inner central part 30 occupies part of the internal volume defined by the inside of the coil 3. The housing 7 is formed in this inner part 30 of the cylinder head 5. As in the other embodiments, the cylinder head 5 comprises a wall 50 which surrounds the outer wall of the coil 3. In the variant of the fifth embodiment shown in Figure 5, an opening 29 is formed between the inner wall 30 and a branch 50a. The branch 50a extends from the outer wall 50 to the inner wall 30 of the yoke 5 at the inner wall portion 30 located near the opening of the housing 7. The inner surface of the opening 29 is therefore formed by the end of the branch 50a of the yoke 5 on the one hand and by the outer surface 32 of the inner wall 30 of the yoke 5 located at the opening of the housing 7. In addition, the radial protrusion 21 includes a protrusion 31 which extends towards said opening 29 when the movable portion 9 is in the first stable position. The protuberance 31 is configured to protrude into said opening 29 during translational movement of the movable part 9 towards the second stable position, to form with the inner surface of the opening 29 a constant air gap zone with facing surfaces. variables. The outer surface 22 of the yoke 5 located at the periphery of the inlet of the housing 7 is formed by the rim of the inner wall 30. The rim of the inner wall 30 and the portion of the radial protrusion 21 located in opposite the rim form a variable gap zone. As in the other embodiments, these air gap zones are also external to the internal volume defined by the inside of the coil 3. To avoid the appearance of an air gap zone in the internal volume defined by the coil 30 3, the movable portion 9 may comprise a nonmagnetic portion 90 configured to be received BRT1056 (CFR0573) - 1 0 - in the portion of the housing 7 included in this internal volume. The non-magnetic portion 90 is made integral with the radial protrusion 21 by overmolding or by any other fastening means. However, the movable portion 9 may be integrally of magnetic material, as illustrated in the previous embodiments. The gap zone, formed in the internal volume by the inner wall 30 and the mobile part 9, then produces a leak which slightly parasitizes the performance of the actuator 1. According to an alternative embodiment shown in FIG. radial protrusion 21 extends radially beyond the protuberance 31 to form an additional variable airgap zone 10 between the surface 24 of the radial protrusion 21 and a surface 22 'of the branch 50a peripheral to the opening 29 Thus, for all embodiments, the power supply of the coil 3 by power supply means such as a generator or a battery produces the appearance of a magnetic flux between the yoke 5 and the part mobile 9, said magnetic flux being induced by the current flowing in the coil 3. This magnetic flux, through the air gap zones, causes the displacement in translation of the movable portion 9 towards the bottom 1 6 of the housing 7 of the cylinder head 5 until the movable portion 9 comes into abutment which corresponds to an active stable position, said second position. The zones of constant airgap with variable viewing surfaces make it possible to limit the energy consumption to move the mobile part 9 when the mobile part 9 is in its stable rest position, called the first position, or a position close to its position. stable rest position. The variable airgap zones in turn make it possible to limit the energy consumption in order to keep the mobile part 9 in its second active stable position or to drive the mobile part 9 into its active stable position when said mobile part 9 is close to its second stable stable position. In addition, the positioning of the gap zones outside the internal volume defined by the inside of the coil 3 makes it possible to maximize the diameter of the mobile part 9 located inside said internal volume and thus to maximize the flow Thus, in the embodiments shown, the gap zones are preferably BRT 1056 (CFR0573) located outside the internal volume defined inside the coil. 3. On the other hand, when the movable portion 9 comprises a central orifice 13, care should be taken to minimize the diameter of this central orifice 13 so as to minimize the section of the movable portion 9 and maximize the flow of the magnetic flux. in the moving part 9.

Moreover, for all the embodiments, the guide 11 can be dispensed with, the guide in translation being able to be ensured by the housing 7. The spring 15 can also be arranged differently, for example outside the cylinder head 5. as shown in FIG. 7, for example. In this embodiment, a pusher 33 is disposed at the end of the mobile part 9 located towards the bottom 16 of the housing 7.

The yoke 5 comprises a hole in the bottom 16 of the housing 7 which allows the pusher 33 to protrude outside the yoke 5 and to bear against the spring 15. The spring 15 is compressed when the movable part 9 is moved in translation to the bottom 16 of the housing 7. Such an architecture can be implemented in all the embodiments described above.

It should also be noted that the movable part 9 can also comprise, at the level of the surfaces forming a variable gap zone with the yoke 5, permanent magnets which can either contribute to keeping the moving part 9 in the first stable rest position or contribute to move and maintain the moving part 9 in the second active stable position. Thus, the different embodiments of the present invention make it possible, due to their constant air gap zone with variable viewing surfaces located outside the internal volume defined by the inside of the coil, to obtain efficient linear actuators 1. in energy and allowing effective actuation on displacements greater than 0.5mm. In addition, the combination with variable airgap zones also located outside the internal volume allow an efficient and effective actuation over the entire stroke of the actuator 1. Such actuators are particularly suitable for applications related to motor vehicle engines. An example of a particular application relates to Canister solenoid valves. Such a solenoid valve is shown in Figure 8 and is intended to be connected to a canister, that is to say an active carbon filter, which stores gasoline vapors. The solenoid valve of Canister 35 comprises an inlet nozzle 37 for purging gases from the canister, a BRT 1056 (CFR0573) -12- body 39 enclosing the electromagnetic linear actuator, an outlet nozzle 41 connected to the manifold intake of the engine to allow the recycling of gases from the canister in the intake circuit, and a connector 43 which provides power to the valve 35 and in particular the coil of the electromagnetic actuator.

FIG. 9 represents an exemplary embodiment of the actuator 1 located inside the solenoid valve of Canister 35 and based on the embodiment of FIG. 6. A membrane 45 is fixed on the outer end of the part mobile 9 of the actuator 1. This membrane 45 is positioned at the inlet of the outlet nozzle 41 and seals the solenoid valve 35 when the actuator 1 is in a stable position of rest. The actuator 1 also comprises a pin 47 which serves to fix and supply the actuator 1. Thus, the power supply of the coil causes the displacement of the movable part, the membrane 45 is then detached from the wall of the outlet nozzle 41 so that the gases can exit the solenoid valve 35 through the outlet nozzle 41 to be recycled into the intake circuit. The actuators presented above are also suitable for other applications. For example, the actuator 1 can be used in valves, and in particular the exhaust gas recirculation valves in which the actuator 1 makes it possible to control the opening and closing the valve. In applications for motor valves, the actuator 1 can be used to control the positioning of a mechanical pin which causes the mechanical coupling or decoupling between a cam and the valve, as shown for example in the FR2971012 application of the applicant. For example, when the actuator is in the rest position, the pin is engaged and the valve is opened by the passage of the cam and when the actuator is in the active position, the pin is removed so that the passage of the cam does not cause the valve to rest, so the valve remains closed. BRT1056 (CFR0573)

Claims (16)

REVENDICATIONS1. Linear electromagnetic actuator (1) comprising: - a yoke (5) which serves to support a coil (3), said coil (3) being configured to be connected to power supply means, - a movable part (9) guided in translation in a housing (7) of the yoke (5), said housing (7) being located at least partially in an internal volume defined by the inside of the coil (3) and extending along the longitudinal axis the coil (3), - an elastic means (15) configured to position the movable part (9) in a first stable rest position in the absence of supply of the coil (3), the coil (3) being configured to cause the translational movement of the movable portion (9) to a second stable position under the effect of a magnetic flux created by the supply of the coil (3), the actuator (1) comprising at least one gap zone between the cylinder head (5) and the movable part (9), characterized in that at least one air gap zone is a constant air gap zone with variable facing surfaces and is located outside the internal volume defined by the inside of the coil (3). 2. An actuator (1) according to claim 1, wherein the constant gap zone with variable facing surfaces is defined by two surfaces respectively belonging to the yoke (5) and the movable part (9), such that, when the moving part (9) is moved from the first to the second position, the area of their facing portions varies and the distance separating said surfaces remains constant. 3. Actuator (1) according to claim 1 or 2 wherein the yoke (5) comprises a cavity (8) extending along the axis of the coil (3) and outside the internal volume defined by the inside the coil (3), and wherein one end (19) of the movable part (9) is configured to protrude into said cavity (8) during its displacement in translation towards the second stable position, the peripheral surface (20) of the movable part (9) and the lateral surface (18) of the cavity (8) forming a constant air gap area with variable viewing surfaces. 4. Actuator (1) according to one of the preceding claims wherein the movable portion (9) has a first portion having a greater cross-sectional area BRT 1056 (CFR0573) than a second portion, and wherein the yoke (5) comprises a shoulder (25) configured to face the first portion during translational movement of the movable portion (9) to the second stable position, the surfaces of said first portion and the first portion shoulder (25) facing each other forming a constant air gap zone with variable facing surfaces. 5. Actuator (1) according to claim 4 wherein the shoulder (25) is at the part of the yoke (5) defining the entrance of the housing (7). 6. An actuator (1) according to claim 4 or 5, wherein the second portion is defined by a radial recess (23) of the movable portion (9) and / or the first portion is defined by a radial over-thickness (27). ) of the movable part (9). 7. Actuator (1) according to one of the preceding claims wherein the movable portion (9) extends outside the housing (7) of the yoke (5) and wherein the portion outside the yoke (5) comprises a radial protuberance (21) extending beyond the surface defined by the entrance of the housing (7). 8. Actuator (1) according to one of the preceding claims, wherein the yoke (5) comprises an inner wall (30) which extends at least partially in the internal volume defined inside the coil (3) to define the housing (7). 9. Actuator (1) according to claims 7 and 8, wherein the yoke (5) comprises an outer wall (50) which surrounds an outer wall of the coil (3), said outer wall (50) comprising a branch (50a). ) extending towards the inner wall (30); wherein an opening (29) is provided between the inner wall (30) and said leg (50a); and wherein the radial protuberance (21) of the movable portion (9) comprises a protuberance (31) which is configured to protrude into said opening (29) during translational movement of the movable portion (9) to the second stable position, the lateral surfaces of the protuberance (31) and the inner surface of the opening (29) facing each other forming a constant gap zone and variable facing surfaces. 10. Actuator (1) according to one of the preceding claims comprising BRT1056 (CFR0573) -15- also at least one zone with variable air gap. 11. An actuator (1) according to claim 10, wherein the variable gap zone is defined by two facing surfaces respectively belonging to the movable part (9) and to the yoke (5), such that, when the moving part ( 9) is moved from the first to the second position, the distance separating said surfaces varies and the area of their opposite portions remains constant. 12. An actuator (1) according to claim 10 or 11 wherein the at least one zone with variable air gap is located outside the internal volume defined by the inside of the coil (3). 13. An actuator according to one of claims 10 to 12 in combination with claim 7 wherein said radial protuberance (21) is configured to form a variable air gap area with the surface of the yoke (5) peripheral to the inlet of the housing (7). 14. A motor valve disconnecting device comprising an actuator (1) according to one of the preceding claims wherein the actuator (1) is configured to allow or not the actuation of the valve by a cam. 15. Solenoid valve (35) comprising an actuator (1) according to one of claims 1 to 13 wherein the actuator (1) is configured to control the opening and closing of the solenoid valve (35). 16. Exhaust gas recirculation valve comprising an actuator (1) according to one of claims 1 to 13 wherein the actuator (1) is configured to control the opening and closing of the valve. BRT 1056 (CFR0573)