Patent Application
20170309399
The present invention relates generally to roll-forming and, more specifically, to a method of roll-forming with gap fillers for a solenoid used for a transmission.
Conventional vehicles known in the art typically include an engine having a rotational output that provides a rotational input into a transmission such as an automatic transmission for a powertrain system of the vehicle. The transmission changes the rotational speed and torque generated by an output of the engine through a series of predetermined gearsets to transmit power to one or more wheels of the vehicle, whereby changing between the gearsets enables the vehicle to travel at different vehicle speeds for a given engine speed.
In addition to changing between the gearsets, the automatic transmission is also used to modulate engagement with the engine, whereby the transmission can selectively control engagement with the engine so as to facilitate vehicle operation. By way of example, torque translation between the engine and the automatic transmission is typically interrupted while the vehicle is parked or idling, or when the transmission changes between the gearsets. In conventional automatic transmissions, modulation is achieved via a hydrodynamic device such as a hydraulic torque converter. However, modern automatic transmissions may replace the torque converter with one or more electronically and/or hydraulically actuated clutches (sometimes referred to in the art as a “dual clutch” automatic transmission). Automatic transmissions are typically controlled using hydraulic fluid, and include a pump assembly, one or more hydraulic solenoid valves, and an electronic controller. The pump assembly provides a source of fluid power to the solenoid valves which, in turn, are actuated by the controller so as to selectively direct hydraulic fluid throughout the automatic transmission to control modulation of rotational torque generated by the output of the engine. The solenoid valves are also typically used to change between the gearsets of the automatic transmission, and may also be used to control hydraulic fluid used to cool and/or lubricate various components of the transmission in operation.
One type of solenoid for the solenoid valves includes a coil, a sleeve, a connector, and a can. An example of such as solenoid is disclosed in U.S. Pat. No. 8,528,599 to Morgan et al. In this solenoid, a solenoid portion includes a solenoid housing or can enveloping a bobbin coil assembly (including a bobbin member and a coil member). The bobbin coil assembly envelopes an armature assembly (including a selectively movable armature member and a stem or pin member extending therefrom). A sleeve member envelopes the armature member. The sleeve member and the armature member define a dampening portion within the interior of the sleeve member. A pole piece member is preferably provided in proximity to a valve portion and is spaced and opposed from the dampening portion. A terminal member extends from the bobbin member, and is preferably in communication with one or more electrical conduction members (e.g., wires) associated with the insulator member.
It is known to use roll-forming by manufactures for various products. Roll-forming is a process where manufacturers apply loads slowly using rollers to bend components, thereby imparting less load on the components being formed and reducing the risk of damage to the components. An example of roll-forming is disclosed in U.S. Pat. No. 4,706,488 to Williamson, the entire disclosure of which is hereby incorporated by reference. When using roll-forming, a continuous surface is strongly preferred because gaps will introduce impact loads/tool chatter that can shorten tool life or cause damage to the finished component.
Therefore, it is desirable to integrate one or more components in a solenoid to help fill in the gaps so that the rollers see a more continuous surface. It is also desirable to provide material in a gap to act as a gap filler that is capable of absorbing the roll-forming load and deforming with the roll-formed surface. Thus, there is a need in the art to provide a method of roll-forming with gap fillers for a solenoid used with a transmission.
The present invention provides a method of roll-forming with gap fillers for a solenoid used with a transmission. The method includes the steps of providing a can of a solenoid, the can having a discontinuous surface with a gap, providing additional material in the gap, and roll-forming the additional material in the gap simultaneously with roll-forming the can to maintain a smooth path for rollers during roll-forming of the solenoid.
One advantage of the present invention is that a new method of roll-forming with gap fillers for a solenoid used with a transmission is provided. Another advantage of the present invention is that the method integrates one or more components to help fill in the gaps in the roll formed surface so that the rollers see a more continuous surface. Yet another advantage of the present invention is that the method uses material to act as a gap filler that is capable of absorbing the roll-forming load and deforming with the roll-formed surface. Still another advantage of the present invention is that the method improves the quality of a non-continuous roll-formed joint.
Other objects, features, and advantages of the present invention will be readily appreciated as the same becomes better understood after reading the subsequent description taken in connection with the accompanying drawings wherein:
Referring now to the figures, where like numerals are used to designate like structure unless otherwise indicated, a solenoid is generally indicated at 10 in
Referring to
The connector 18 is generally rectangular in shape, but may be any suitable shape. The connector 18 includes a first flange 19 extending circumferentially therefrom and a second flange 20 extending radially therefrom. The first flange 19 extends over a portion of the can 12 and the second flange 20 extends into the gap 14. The connector 18 extends radially and axially from the sleeve 16. The sleeve 16 may be made of a plastic material or a metal material. It should be appreciated that the sleeve 16 and connector 18 may be integral and one-piece. It should also be appreciated that the sleeve 16 and connector 18 are both installed from the axial end of the can 12 with the gap 14. It should further be appreciated that the solenoid 10 may be of a type employed in a conventional transmission of a powertrain system for a vehicle.
Referring to
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The flange 26 has a roll-formed surface 34 formed by the roll-forming method. In one embodiment, the sleeve 16 may be a dummy member made of a plastic material. The additional material 22 is made of a plastic material and is part of the sleeve 16. It should be appreciated that the additional material 22 and sleeve 16 are integral, unitary, and formed as one-piece.
The solenoid 10 includes a pole piece member (not shown) and a bobbin (not shown) disposed about the pole piece member and the can 12 encloses the bobbin. The bobbin has a primary electromagnetic coil (not shown) wound thereon to create a magnetic field when energized. The solenoid 10 also includes the connector 18 for connecting with the electromagnetic coil and to ground (not shown). It should be appreciated that the connector 18 receives a continuous variable, digital control signal from a primary driver (not shown) such as the electronic controller (not shown).
Referring to
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The bobbin assembly 140 includes additional material 122 extending axially and circumferentially from the bobbin 142. The additional material 122 extends into the gap 114. The additional material 122 may be any material, such as a plastic material or metal material, capable of absorbing a roll-forming load and deforming with a roll-formed surface to be described. It should be appreciated that the purpose of the additional material 122 is to integrate one or more separate components to help fill in the gap 114 so that the rollers see a more continuous surface during roll-forming of the can 112. It should be appreciated that the winding towers 144 of the connector 118 would have to be cut off before roll-forming. It should also be appreciated that the bobbin assembly 140 is installed from the axial end of the can 112 with the gap 114. It should further be appreciated that the additional material 122 is molded into the bobbin 142 to make a path for the rollers between the edges of the opening or gap 114 in the can 112. It should also be appreciated that, when using roll-forming, a continuous surface is strongly preferred because gaps will introduce impact loads/tool chatter that can shorten tool life or damage the finished component.
Referring to
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Accordingly, the present invention provides a method, according to the present invention, for roll-forming with gap fillers for the can 12, 112 of the solenoid 10, 110 used for a transmission. The method includes the steps of providing the can 12, 112 of the solenoid 10, 110. The can 12, 112 has a discontinuous surface 36, 136 with a gap 14, 114. The method also includes the steps of providing the connector 118, bobbin 142, pole-piece 123, and sleeve 116 and installing the bobbin 142, connector 18, 118, and sleeve 16, 116 in the gap 14, 114 from an axial end of the can 12, 112. The method includes the steps of providing additional material 22, 122 in the gap 14, 114. The additional material 22, 122 is either one of a plastic material and a metal material capable of absorbing a roll-forming load and deforming with a roll-formed surface 34, 134. The method further includes the steps of roll-forming the additional material 22, 122 in the gap 14, 114 simultaneously with roll-forming the can 12, 112 to maintain a smooth path for the rollers and securing the sleeve 16, 116, bobbin 142, and the connector 18, 118 to the can 12, 112 during roll-forming for the solenoid 10, 110.
The present invention has been described in an illustrative manner. It is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation.
Many modifications and variations of the present invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the invention may be practiced other than as specifically described.
