Pressure solenoid control valve with flux shunt

• US 6,029,703 A
• Filed: 12/18/1998
• Issued: 02/29/2000
• Est. Priority Date: 12/18/1998
• Status: Expired due to Term

• Current Assignee: Borg-Warner Automotive Incorporated (BorgWarner Incorporated)
• Original Assignee: Borg-Warner Automotive Incorporated (BorgWarner Incorporated)
• Inventors: Holmes, Garrett R., Erickson, Bradley C.
• Primary Examiner(s): Michalsky, Gerald A.
• Application Number:
  US09/216,135
• Time in Patent Office: 438 Days
• Field of Search: 137/625.61, 137/625.64, 137/625.65, 251/129.15, 251/129.17, 251/129.18
• US Class Current: 137/625.61
• CPC Class Codes: F15B 13/0442 with proportional solenoid allowing stable intermediate positions
• CPC Class Codes: F16K 31/0613 with cylindrical slides
• CPC Class Codes: Y10T 137/8659 Variable orifice-type modulator
• CPC Class Codes: Y10T 137/86614 Electric

Abstract

A solenoid control valve (10) that includes an electromagnetic coil (30) positioned within a housing (16) and a spool valve (72) positioned within a central bore (70) of a valve body (20). An armature (40) is axially positioned within the coil (30) and an armature spring (52) biases the armature (40) against an opening in the central bore (70) when the coil (30) is not energized. The spool valve (72) includes an internal chamber and a pair of sealing lands (98,100) that selectively seal a supply port (92) and a control port (94) within the valve body (20). A pole piece (26), including an annular flux shunt portion (62), is threadably engaged with the housing (16) to control a working air gap (60) between the pole piece (26) and the armature (40). The flux shunt portion (62) more radially directs the electromagnetic field lines to weaken the magnetic force as the armature (40) moves closer to the pole piece (26). A deep drawn flux tube (64) is positioned within the housing (16), and the flux tube (64) and the housing (16) are attached to the valve body (20) by a crimped connection (22) at a common location.

Claims

1. A solenoid control valve comprising:

a housing defining an internal chamber therein;

an electromagnetic coil wound on a bobbin and coaxially mounted within the housing relative to the internal chamber;

a movable armature positioned within the bobbin in the internal chamber and having a first end and a second end;

an armature spring in contact with the first end of the armature, said armature spring biasing the armature to a first position within the internal chamber and said armature being movable from the first position to a second position against the bias of the spring upon energizing of the electromagnetic coil;

a pole piece mounted to the housing and positioned adjacent to the first end of the armature and defining an air gap therebetween, said pole piece including a flux shunt piece being an annular flange extending towards the armature, said flux shunt piece causing electromagnetic field lines from the coil to extend radially from the armature when the electromagnetic coil is energized so as to weaken the magnetic force on the armature when the armature moves toward the pole piece to the second position;

a deep drawn flux tube secured to the bobbin and the housing and acting to define the electromagnetic field lines from the electrical magnetic coil, said flux tube including an annular flange extending around a bottom portion of the tube; and

a valve body assembly including a supply port, an exhaust port and a control port, said valve body assembly including a central bore axially aligned with the armature and in fluid communication with the supply port, exhaust port, and the control port, said valve body assembly including a spool valve disposed within the central bore, said valve body assembly further including a spool valve spring that biases the spool valve towards the armature, said flux tube and said housing being connected to the valve body assembly by a plurality of crimped tabs, said annular flange being positioned between the housing and the valve body assembly and said crimped tabs extending from the housing over the flange and being crimped to the valve body assembly.

2. The control valve according to claim 1 wherein the first end of the armature is positioned within an opening defined by the flux shunt piece when the armature is in the second position.

3. The control valve according to claim 1 wherein the pole piece is threadably connected to the housing so as to control the distance of the air gap between the pole piece and the armature.

4. The control valve according to claim 1 wherein the pole piece and the flux shunt piece are a single member fabricated from a piece of metal.

5. The control valve according to claim 1 wherein the bobbin is a molded plastic member.

6. The control valve according to claim 1 wherein the valve body assembly includes an opening in fluid communication with the central bore and said spool valve includes a central chamber in fluid communication with the central bore of the valve body assembly, said second end of the armature seating against the valve body assembly when the armature is in the first position to seal the central bore.

7. The control valve according to claim 6 wherein the supply port is in fluid communication with the central chamber of the spool valve so that the spool valve moves away from the electromagnetic coil against the bias of the valve spring when a source pressure is applied to the supply port.

8. The control valve according to claim 1 wherein the control valve is a control valve used in the transmission of a vehicle.

9. A solenoid control valve comprising:

a housing defining an internal chamber therein;

an electromagnetic coil wound on a bobbin and coaxially mounted within the housing relative to the internal chamber;

a movable armature positioned within the internal chamber and having a first end and a second end, said armature being movable between a first position and a second position;

a flux tube secured to the bobbin and acting to define the electromagnetic field lines from the electromagnetic coil, said flux tube being a deep drawn metal member and including an annular flange extending around a bottom portion of the flux tube; and

a valve body assembly including a valve body having a central bore axially aligned with the armature, said valve body defining a supply port, an exhaust port and a control port in fluid communication with the central bore, said valve body assembly further including a spool valve disposed within the central bore and a spool valve spring, said spool valve spring biasing the spool valve towards the armature, said flux tube and housing being connected to the valve body by a series of crimped tabs, said annular flange being positioned between the housing and the valve body and said crimped tabs extending from the housing over the flange and being crimped to the valve body.

10. The control valve according to claim 9 further comprising a pole piece mounted to the housing and positioned adjacent to the first end of the armature and defining an air gap therebetween, said pole piece including a flux shunt piece being an annular flange extending towards the armature, said flux shunt piece causing the electromagnetic field lines from the coil to extend radially from the armature when the electromagnetic coil is energized so as to weaken the magnetic force on the armature when the armature moves towards the pole piece to the second position.

11. The control valve according to claim 10 wherein the pole piece is threadably connected to the housing so as to control the distance of the air gap between the pole piece and the armature.

12. The control valve according to claim 10 wherein the pole piece and the flux shunt piece are a single member fabricated from a piece of metal.

13. A solenoid control valve for controlling a fluid pressure in a vehicle transmission, said control valve comprising:

a housing defining an internal chamber therein;

an electromagnetic coil wound on a bobbin and coaxially mounted within the housing relative to the internal chamber;

a movable armature positioned within the bobbin in the internal chamber and having a first end and a second end;

an armature spring in contact with the first end of the armature, said armature spring biasing the armature to a first position within the internal chamber and said armature being movable from the first position to a second position against the bias of the spring when the electromagnetic coil is energized;

a pole piece threadably mounted to the housing and positioned adjacent to the first end of the armature and defining an air gap therebetween, said pole piece including a flux shunt piece being an annular flange extending towards the armature, said pole piece being threadably connected to the housing so as to control the distance of the air gap between the pole piece and the armature, said flux shunt piece causing electromagnetic field lines from the coil to extend radially from the armature when the electromagnetic coil is energized so as to weaken the magnetic force on the armature when the armature moves towards the pole piece to the second position;

a deep drawn flux tube secured to the bobbin and the housing, and acting to define the electromagnetic field lines from the electromagnetic coil, said flux tube including an annular flange extending around a bottom portion of the tube; and

a valve body assembly including a valve body having a central bore axially aligned with the armature, said valve body defining a supply port, an exhaust port and a control port in fluid communication with the central bore, said valve body assembly further including a spool valve and a spool valve spring disposed within the central bore, said spool valve spring biasing the spool valve towards the armature, said spool valve being axially positioned within the central bore, said flux tube and said housing being connected to the valve body at a common location by a plurality of crimped tabs, said annular flange being positioned between the housing and the valve body and said crimped tabs extending from the housing over the flange and being crimped to the valve body.

14. The control valve according to claim 13 wherein the first end of the armature is positioned within an opening defined by the flux shunt piece when the armature is in the second position.

15. The control valve according to claim 13 wherein the pole piece and the flux shunt piece are a single member fabricated from a piece of metal.