[0001] The present invention in general relates to an electromagnetic actuator and in particular to an assembly for an electromagnetic actuator.

[0002] In general, a bobbin is used to house a coil. The bobbin has a tubular body with or without flanges on both the sides of the body. A pair of limbs are attached to base of one of the flanges. The coil has two ends, one end entering the bobbin housing through a limb and after completion of winding the other end is configured to exit the bobbin. The exit end of the coil is not well supported, thus causing tension in the coil. Therefore, the coil unwinds causing difficulties at the time of assembling.

[0003] There is hence a need for a bobbin with a support member that facilitates support to the coil exit end and to securely route it through the limbs and to eliminate the aforementioned problems.

[0004] In many embodiments, an assembly comprising a bobbin and a coil arranged on the bobbin for an electromagnetic actuator system in an automobile is disclosed. The bobbin having at least one flange and at least a pair of limbs attached to one of the at least one flange to support coil ends entering and exiting onto the bobbin. The at least one flange comprising at least one guiding member to guide the coil from the at least one flange or to the limbs. The guiding member includes a slope portion, extending from the at least one flange to one of the limbs, for supporting the coil and a side portion, wherein the coil is in contact with the slope portion and the side portion.

[0005] In one embodiment each of the at least a pair of limbs comprises, an enclosing member disposed along the length of the each of the at least a pair of limbs, to securely guide the coil ends entering and exiting the bobbin.

[0006] In another embodiment, the side portion is wedge shaped, pyramidal or conical, with a base of the side portion proximal to the one of the at least one pair of limbs. [0007] In yet another embodiment, the guiding member is formed on the flange on the exit end of the coil.

[0008] In a further embodiment, the guiding members formed on the flange on the exit end of the coil and entry end of the coil.

[0009] In some embodiments, the height of one end of the slope portion adjacent to the flange is in the range of 1 to 1.2 mm and the height of other end of the slope portion adjacent to one of the at least a pair of limbs is in the range of 0.4 to 0.5 mm.

[0010] In several embodiments, length of the enclosing member along an axis A is in the range of 7 to 12 mm.

[0011] In many embodiments, width of the enclosing member perpendicular to the axis A is in the range of 0.5 to 0.9 mm.

[0012] In some embodiments, the bobbin is injection moulded along with guiding member.

[0013] In an embodiment, the coil ends are connected to respective lead frames. [0014] A solenoid valve for guiding of fuel vapours in an automobile is provided in several embodiments. A housing, wherein the housing having a fluid inlet opening and a fluid outlet opening is provided. An assembly according to the aforementioned assembly is assembled. A seat, wherein the seat is adjacent to one end of a magnetic core of the bobbin, and along an axis of the magnetic core between a first position for opening and a second position for closing the fluid outlet opening is provided.

[0015] Other characteristics, details and advantages of the invention can be inferred from the description of the invention hereunder. A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying figures, wherein:

[0016] FIG. 1 A depicts a bobbin housing a coil according to the invention,

[0017] FIG. IB shows a guiding member, [0018] FIG. 1C represents the enclosing member,

[0019] FIG. ID depicts a bobbin with housing for a coil according to a variant of the invention,

[0020] FIG. 2 depicts a longitudinal sectional view of a canister purge valve with the bobbin according to the invention.

[0021] It must be noted that the figures disclose the invention in a detailed enough way to be implemented, said figures helping to better define the invention if need be. The invention should however not be limited to the embodiment disclosed in the description.

[0022] The invention in its various embodiments discloses an assembly 10 with a bobbin 100, and a coil 101 arranged on the bobbin 100, for an electromagnetic actuator system in an automobile. The bobbin 100 is provided with at least one flange 103. The bobbin 100 is further provided with at least a pair of limbs 105, attached to one of the at least one flange 103, to support ends 101a, 101b of the coil 101 entering and exiting the bobbin 100, as shown in FIG. 1A. The bobbin 100 includes a body along axis A of the assembly to house the coil 101.

[0023] In some embodiments, the bobbin 100 is provided with a pair of support flanges 103 arranged on both ends of the body perpendicular to axis A of the bobbin 100. In many embodiments the bobbin 100 has a pair of limbs 105 formed on flange 103, as illustrated in FIG. 1A. In some embodiments, at least one flange 103 is provided with a guiding member 110, to guide the coil 101. The guiding member 110 is extended from the at least one flange 103 or the guiding member is extended to the limbs 105. The guiding member 110 is disposed between the flange 103 adjacent to the limbs 105. In other words, the guiding member 110 extends from one side of the flange 103 and ends adjacent to the limbs 105.

[0024] In some embodiments, the guiding member 110 is formed on the flange 103 on exit end of the coil 101b or on both coil entry and exit ends of the coil 101a, 101b. The guiding member 110 is sensibly in the plan of the flange 103. The guiding member 110 includes a slope portion 113, that is designed to extend from the at least one flange 103 to one of the limbs 105. The slope portion 113 is provided for supporting the coil 101, in a direction along an axis A of the bobbin 100. A side portion 111 is disposed on the guiding member 110. The slope portion 113 provided on the guiding member 110, is designed in a way that it inclines from one end of the flange 103 to the limbs 105. The side portion 111 is formed on the slope portion 113. The side portion 111 is provided as a protrusion, to enable shifting of direction of the coil 101. Furthermore, the side portion 111 is provided to offer support to the coil 101. The slope portion 113 conveniently accommodates the coil 101, providing sufficient support and guidance. The guiding member 110, is thus fabricated to facilitate, support and route the coil 101 from the flange 103 towards one of the limbs 105. The guiding member 110 is as shown in FIGs. 1 A to IB.

[0025] In some embodiments, the side portion 111 is a wedge-shaped member, a pyramidal, or a conical shaped member as shown in FIGs. 1A to IB. The side portion 111 is designed to have a variable width profile with a wider end of the side portion 111 facing the limbs and an other end of the side portion 111 adjacent the flange 103. The sharp edge of the side portion 111 is designed to face or extend from the flange 103. The flat surface of the side portion 111 is designed to face or extend towards the limbs 105.

[0026] In many embodiments, the slope portion 113 is designed to have a variable height profile. The height of one end of the slope portion 113 adjacent to the flange 103 is in the range of 1 to 1.2 mm. The height of other end of the slope portion 113 adjacent to one of the at least a pair of limbs 105 is in the range of 0.4 to 0.5 mm. [0027] In several embodiments, the at least a pair of limbs 105 comprise an enclosing member 107 thereby forming a channel as shown in FIG. 1A. The enclosing member 107 is disposed along the length of the limbs 105 to cover and safeguard the coil ends 101a, 101b entering and exiting the bobbin 100.

[0028] In many embodiments, the enclosing member 107 is disposed along the height or length of the limbs 105. The length or height along axis A of the bobbin 100 is in the range of 7 to 12 mm. The length or height of the bobbin 100 is preferably 9 mm. [0029] In some embodiments, breadth of the enclosing member 107 is in the range of 0.5 to 0.9 mm. The breadth of the enclosing member 107 is preferably 0.7 mm. The thickness of the enclosing member 107 is in the range of 0.2 to 0.5 mm. The length, breadth and thickness of the enclosing member 107 is not restricted to the aforementioned ranges.

[0030] In several embodiments, the enclosing member 107 is disposed on the limbs 105 of the bobbin 100 to form a channel. The enclosing member 107 is formed on both the limbs 105. The enclosing member 107 is formed on the side of the limb facing the other limb in a way that the enclosing member 107 is parallel to the other limb and to the enclosing member 107 on the other limb. The enclosing member 107 is an elongated member formed along the axis A of the bobbin. The enclosing member 107 follows the profile of the limbs as shown in FIG. 1A. An end of the enclosing member 107 away from the flange 103 is curved over each of the at least a pair of limbs 105 forming an acute angle with the limbs 105. The enclosing member 107 after separation from the limbs 105 is represented in FIG. 1C. In an alternate embodiment, the enclosing member is formed only along one limb of the pair of limbs 105.

[0031] In many embodiments, a coil 101 is fixed to a lead frame 109 on one end that is entry end 101a of the coil 101, and is allowed to enter the bobbin 100 through one of the pair of limbs 105. The coil 101 enters the body through the limbs 105 and flange 103, to be housed on the body of the bobbin 100, as aforementioned in previous embodiments. The guiding member 110 on the exit end guides the coil 101b out of the bobbin 100. The coil 101 shifts the direction due to the side portion 111 that protrudes and the coil 101 rests sufficiently on the side portion 111 and inclines down to the limbs 105. The coil 101 from the exit end is securely guided by the guiding member 110 and is fed into the channel formed by limbs 105 and enclosing member 107 and exits the limbs 105 and is fixed to the lead frame 109 on the other side.

[0032] In some embodiments, one end of the bobbin 100 is supported. In alternate embodiments the guiding member 110 is formed on both ends of the coil on the flange 103 (not shown in Figures). A guiding member 110 is provided on the coil exit end to guide the coil towards the axis A. Further, a guiding member 110 is provided on the entry end to guide the coil 101 away from the axis A.

[0033] In some embodiments, material of the bobbin 100 is selected from a group of materials containing a polymer or a metal. The polymer is selected from one of thermoplastics or thermosetting plastics. Preferably polyamide 6 reinforced with 35 % glass fibre (PA6 GF35) which is one of thermoplastics is included. However, the material of the assembly is not restricted to the aforementioned materials.

[0034] In some embodiments, the mould is fabricated based on desired bobbin design. The material of the bobbin 100 is selected from aforementioned materials to obtain the bobbin 100. The material is injected into the mould to obtain the bobbin 100. The bobbin 100 along with the guiding member 110 is made by injection moulding process.

[0035] In several embodiments, the base portion 111 is inclined axially or in the direction of the axis A of the bobbin 100, on one of a pair of flanges 103.

[0036] FIG. ID shows a variant of the bobbin realization. In this variant, the coil is not shown. The main difference with the previous mode of realization is at the junction between the flange 103’ and the pair of limbs 105’. It can be seen that the guiding member 110’ is not sensibly in the plan of the flange 103’ but sloped between the flange 103’ and the pair of limbs 105’. The elements with the same numerical references being identical, their functions will not be repeated here. [0037] The invention in its several embodiments provide a solenoid valve 200 for guiding of fuel vapours in an automobile and more particularly a canister purge valve (CPV) as illustrated in FIG.2. The solenoid valve 200 includes a housing 201. The housing 201 is provided with a fluid inlet opening 202 and a fluid outlet opening 204. Assembly 10 that comprises a bobbin 100 and a coil 101 as aforementioned is provided in the housing 201. The assembly 10 comprising a bobbin 100 and a coil 101 arranged on the bobbin 100. A magnetic core 208 is provided along the bobbin 100. A seat 206, which is adjacent to one end of the magnetic core 208 of the bobbin 100 and along an axis X of the magnetic core 208, is disposed. The seat 206 is disposed between a first position for opening and a second position closing the fluid outlet opening 204. [0038] In some embodiments, the solenoid valve 200 is an electromagnetic device as disclosed in WO2019243611A1. The device 200 is provided with a fuel vapour inlet duct 202 that is connected to a circulation duct to receive fuel vapours discharged from a fuel tank, and a fuel vapour outlet duct 204. An element 210, that is movable under the electromagnetic effect of the coil 101, is disposed along the axis X of the device 200. This movable element is in the form of a piston 210, made of a ferromagnetic material. The piston 210, is movable axially along the axis X inside the magnetic core 208. The piston 210 is configured to move and exert pressure against a valve seat 206, through which fuel vapours circulate when the device 200 is open. The fuel vapours enter the device 200 through the inlet duct 202 provided, and the fuel vapours exit the device 200, through the valve seat 206 and further through the outlet duct 204 provided.

[0039] In an alternate embodiment, the assembly 10 with the bobbin 100 may be formed without flanges 103. The guiding member 110 is formed on the body of the bobbin 100 (not shown in the figures). In another alternate embodiment, the bobbin has no limbs 105, the guiding member 110 is attached to the flange 103 and end coils are directly clamped to the lead frame 109 which may be directly attached to any part of the bobbin 100 and specifically to the flange.

[0040] In some embodiments, the coil 101 entering and exiting the bobbin 100 is enclosed securely and is further guided in and out of the bobbin 100. The coil 101 which is exposed previously is now sealed from the environment by the enclosing member 107, which further prevents unwinding of the coil 101 thereby preventing slipping of the coil 101 from the limbs 105.

[0041] In some embodiments, the coil 101 is made of a conductive material. The coil 101 material is preferably copper. The coil 101 is preferably insulated, and an enameled copper wire is used. However, the material of the coil 101 is not restricted to enameled copper coil.

[0042] In various embodiments, the bobbin 100 with the guiding member 110 and the enclosing member 107 secures and guides the coil 101 during assembly. Thereby, resulting in reduced assembly time, as the assembly 10 with the bobbin 100, avoids unwinding of the coil. Further tension experienced by the coil at the exit end of the coil 101b is reduced due to the side wall 111 and slope portion 113 of the guiding member 110.

[0043] Various additional modifications of this invention may occur to those skilled in the art. All deviations from the specific teachings of the several embodiments of this specification that basically rely on the principles and their equivalents through which the art has been advanced are properly considered within the scope and ambit of the invention as described and claimed. In the claims, any bracketed reference signs shall not be construed as a limitation of the claim.