Electromagnetic actuator

Abstract

The objective is to provide an electromagnetic actuator used in a parking lock mechanism that can be miniaturized while ensuring sufficient thrust force when releasing the parking lock. [Solution] The electromagnetic actuator 100 according to the present invention comprises a main actuator 100a that pushes and pulls a first output shaft 120, and a sub-actuator 100b that pushes and pulls a second output shaft 150. When the protruding direction of the first output shaft 120 is forward and the retracting direction is backward, the second output shaft 150 is positioned on the same straight line as the first output shaft 120 and behind it. The first stroke S1 of the first output shaft 120 is greater than the second stroke S2 ​​of the second output shaft 150, and the rear of the first stroke S1 and the front of the second stroke S2 ​​overlap.

Description

Technical Field

[0001] The present invention relates to an electromagnetic actuator used in a parking lock mechanism.

Background Art

[0002] In a vehicle, an electromagnetic actuator is used in a parking lock mechanism. For example, Patent Document 1 discloses "a parking lock device including a parking gear fixed to a rotating shaft of a transmission, a parking pole engageable with the parking gear, a parking rod movable forward and backward, a cam member that presses the parking pole against the parking gear and releases the pressing of the parking pole against the parking gear in response to the forward and backward movement of the parking rod, and an actuator for moving the parking rod forward and backward."

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When pulling out the engaging portion of the parking pole from the parking gear when releasing the parking lock, a large thrust greater than the frictional resistance between the parking gear and the engaging portion is required. For this reason, the actuator used in the parking lock mechanism inevitably tends to be large. Then, as a result, the installation space also becomes large, and it is likely to cause restrictions in the layout.

[0005] In view of such problems, an object of the present invention is to provide an electromagnetic actuator that can be downsized while ensuring sufficient propulsive force when releasing the parking lock in an electromagnetic actuator used in a parking lock mechanism. [Means for solving the problem]

[0006] To solve the above problems, a typical configuration of the electromagnetic actuator according to the present invention comprises a main actuator that pushes and pulls a first output shaft and a sub-actuator that pushes and pulls a second output shaft, wherein when the protruding direction of the first output shaft is forward and the retracting direction is backward, the second output shaft is arranged on the same straight line as the first output shaft and behind it, the first stroke of the first output shaft is greater than the second stroke of the second output shaft, and the rear of the first stroke and the front of the second stroke overlap.

[0007] The housing further comprises a second housing chamber formed in the above housing for housing a second output shaft, an intake valve connected to the rear of the second housing chamber for drawing working fluid into the second housing chamber, and a discharge valve connected to the rear of the second housing chamber for discharging working fluid from the second housing chamber, wherein the working fluid is drawn in and discharged in the space at the rear of the second housing chamber by reciprocating the second output shaft.

[0008] The housing further comprises a second housing chamber formed in the above housing for housing a second output shaft, an intake valve connected to the front of the second housing chamber for drawing working fluid into the second housing chamber, and a discharge valve connected to the front of the second housing chamber for discharging working fluid from the second housing chamber, wherein the intake and discharge of working fluid are performed in the space in front of the second housing chamber by reciprocating the second output shaft.

[0009] The housing further comprises a first housing chamber formed in the above-mentioned housing for housing a first output shaft, an intake valve connected to the rear of the first housing chamber for drawing working fluid into the first housing chamber, and a discharge valve connected to the rear of the first housing chamber for discharging working fluid from the first housing chamber, wherein the working fluid is drawn in and discharged in the space at the rear of the first housing chamber by reciprocating the second output shaft. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide an electromagnetic actuator used in a parking lock mechanism that can be miniaturized while ensuring sufficient thrust force when releasing the parking lock. [Brief explanation of the drawing]

[0011] [Figure 1] This is a diagram illustrating the parking lock mechanism. [Figure 2] This is a diagram illustrating the electromagnetic actuator of this embodiment. [Figure 3] This is a diagram illustrating the operation of an electromagnetic actuator. [Figure 4] This is a diagram illustrating the thrust of an electromagnetic actuator. [Figure 5] This is a diagram illustrating the pump operation of an electromagnetic actuator. [Figure 6] This figure illustrates another configuration of the electromagnetic actuator of this embodiment. [Modes for carrying out the invention]

[0012] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. The dimensions, materials, and other specific numerical values ​​shown in these embodiments are merely examples to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0013] Figure 1 is a diagram illustrating the parking lock mechanism 200. As shown in Figure 1, the parking lock mechanism 200 consists of a parking gear 210, a parking pawl 220, a cam 230, a parking rod 240, and the electromagnetic actuator 100 of this embodiment. Figure 1 shows the locked state.

[0014] The parking gear 210 is a gear mounted on the rotating shaft (not shown) of the vehicle's transmission and has multiple teeth 212. The parking pawl 220 is a rotatable lever having a protrusion 222 that meshes with the parking gear 210. The cam 230 is mounted on the end of the parking rod 240 and is connected to the electromagnetic actuator 100 via the parking rod 240. The parking rod 240 moves back and forth in conjunction with the electromagnetic actuator 100, operating the cam 230.

[0015] When the cam 230 is pushed out, the parking pawl 220 is biased against the parking gear 210. The cam 230 is pushed by the parking rod 240 by a spring 232 and engages when the phase between the teeth 212 and the protrusion 222 are aligned. In other words, when locked, the electromagnetic actuator 100 does not require a strong thrust. On the other hand, when the cam 230 is pulled out, for example when the vehicle is parked on a slope, a large load is applied between the teeth 212 and the protrusion 222. As a result, the frictional resistance between them is also large, and a large thrust is required to pull out the parking rod 240.

[0016] Figure 2 is a diagram illustrating the electromagnetic actuator 100 of this embodiment. Figure 2(a) shows the state when the parking lock is engaged. Figure 2(b) shows the state when the parking lock is released.

[0017] As shown in Figures 2(a) and (b), the electromagnetic actuator 100 of this embodiment houses two actuators, a main actuator 100a and a sub-actuator 100b, within a single housing 102. For ease of understanding, in the following description, the protruding direction of the first output shaft 120 (described later) of the main actuator 100a will be referred to as the forward direction, and the retracting direction as the rearward direction.

[0018] The main actuator 100a includes a first coil 110, a first output shaft 120, and a first housing chamber 130, and pushes and pulls the first output shaft 120. The first coil 110 is housed in the housing 102, and a first housing chamber 130 is formed inside the first coil 110. The first output shaft 120 is housed in the first housing chamber 130 and moves forward and backward in the first housing chamber 130 by switching the energization direction of the first coil 110.

[0019] The sub-actuator 100b includes a second coil 140, a second output shaft 150, and a second housing chamber 160, and pushes and pulls the second output shaft 150. The second coil 140 is housed in the housing 102, and a second housing chamber 160 is formed inside the second coil 140. The second output shaft 150 is housed in the second housing chamber 160 and moves forward and backward in the second housing chamber 160 by switching the energization direction of the second coil 140.

[0020] Regarding the reciprocating motion of the sub-actuators 100a and 100b, a configuration may be adopted in which a return spring (not shown) is used to switch the energization and non-energization of the first coil 110 or the second coil 140 to move forward and backward.

[0021] As shown in Fig. 2(a), the main actuator 100a and the sub-actuator 100b are arranged adjacent to each other. And the second output shaft 150 is arranged on the same straight line as and behind the first output shaft 120.

[0022] As a feature of this embodiment, the first stroke S1 of the first output shaft 120 is larger than the second stroke S2 of the second output shaft 150, and the rear of the first stroke S1 and the front of the second stroke S2 overlap. Due to the overlap of the strokes, the first output shaft 120 and the second output shaft 150 can move in a contacting state at the rear (retracting side) of the first stroke S1. In other words, when the first output shaft 120 starts, the second output shaft 150 can reinforce its thrust.

[0023] Figure 3 illustrates the actuator operation of the electromagnetic actuator 100. In Figure 3(a), the electromagnetic actuator 100 is in its initial state, and both the first coil 110 of the main actuator 100a and the second coil 140 of the sub-actuator 100b are de-energized. At this time, the rear end of the first output shaft 120 and the front end of the second output shaft 150 are in contact.

[0024] In Figure 3(b), the electromagnetic actuator 100 is in a state where both the first coil 110 and the second coil 140 have been energized, i.e., in an energization transient state. In the energization transient state, the first output shaft 120 and the second output shaft 150 begin to move together in the protruding direction (forward). The parking rod 240 begins to move due to the combined thrust of the first output shaft 120 and the second output shaft 150.

[0025] Then, when the second output shaft 150 moves for the second stroke S2, it comes into contact with the stopper 162 of the second storage chamber 160, and the movement of the second output shaft 150 to the right is completed. Once the movement of the second output shaft 150 to the right is complete, as shown in Figure 3(c), only the first output shaft 120 moves further in the protruding direction (forward) away from the second output shaft 150. At this time, the parking rod 240 moves only by the thrust of the first output shaft 120, but since it has already passed the range of high frictional resistance, it can move without any problems. Then, when the first output shaft 120 moves for the first stroke S1, the first output shaft 120 stops moving. As a result, the parking lock is released.

[0026] Figure 4 illustrates the thrust of the electromagnetic actuator 100. In the example in Figure 4, the thrust of the sub-actuator 100b is depicted as being slightly less than that of the main actuator 100a. As described above, in the transient state of energization, the first output shaft 120 and the second output shaft 150 move together simultaneously, so the thrust during the second stroke S2 ​​is the resultant force of the main actuator 100a and the sub-actuator 100b. After the second stroke S2, the second output shaft 150 stops, so from the second stroke S2 ​​to the first stroke S1, the thrust of the main actuator 100a becomes the resultant force.

[0027] As described above, the electromagnetic actuator 100 of this embodiment provides greater thrust during the transient energization state (especially during startup) compared to using a single actuator. In this embodiment, the main actuator 100a and the sub-actuator 100b are arranged in the same straight line within the housing 102. As a result, although the length is slightly longer than that of a conventional actuator that can provide the same amount of thrust, the diameter can be significantly reduced. Therefore, it is possible to achieve miniaturization while ensuring sufficient thrust when releasing the parking lock.

[0028] Furthermore, when the first output shaft 120 is in the protruding position (unlocked state), the second output shaft 150 can move without contacting the first output shaft 120. Maintaining the unlocked state does not require a large thrust, so the thrust of the main actuator 100a alone is sufficient.

[0029] Therefore, in this invention, a sub-actuator 100b that can move freely when the lock is released (i.e., when driving) is used to configure a pump for lubrication, cooling, and hydraulic supply.

[0030] As shown in Figure 2, the electromagnetic actuator 100 of this embodiment further includes an intake valve 180 and a discharge valve 190. The intake valve 180 is a check valve, connected to the rear 164 of the second housing chamber 160, and is a valve that draws working fluid into the second housing chamber 160. The discharge valve 190 is also a check valve, connected to the rear 164 of the second housing chamber 160, and is a valve that discharges working fluid from the second housing chamber 160.

[0031] Figure 5 illustrates the pump operation of the electromagnetic actuator 100. After the actuator operation of the electromagnetic actuator 100 described using Figure 3, the main actuator 100a maintains the protruding state by continuing to supply current to the first coil 110. The sub-actuator 100b is made to reciprocate by switching the direction of the current flowing to the second coil 140.

[0032] Figure 5(a) shows the operation of hydraulic fluid suction by the sub-actuator 100b. When the second output shaft 150 moves in the protruding direction (forward), the hydraulic fluid is drawn from the suction valve 180 into the rear part 164 of the second containment chamber 160.

[0033] Figure 5(b) shows the discharge operation of the hydraulic fluid by the sub-actuator 100b. When the second coil 140 of the sub-actuator 100b is energized in the reverse direction from the state shown in Figure 5(a), the second output shaft 150 moves in the retraction direction (rearward) as shown in Figure 5(b). As a result, the hydraulic fluid is discharged from the discharge valve 190 to the rear 164 of the second containment chamber 160. By reciprocating the second output shaft 150 in this way, the hydraulic fluid is drawn in and discharged in the space at the rear 164 of the second containment chamber 160.

[0034] As described above, the sub-actuator 100b of the electromagnetic actuator 100 in this embodiment has the function of assisting the propulsion of the main actuator 100a, as well as the function of a pump that delivers working fluid. Therefore, the pumps used around the electromagnetic actuator 100 for circulating working fluid, cooling, and hydraulic supply can be replaced by the sub-actuator 100b of the electromagnetic actuator 100. This not only makes it possible to miniaturize the electromagnetic actuator 100 itself, but also reduces the cost of the entire device.

[0035] Figure 6 illustrates another configuration of the electromagnetic actuator of this embodiment. In the actuator illustrated in Figure 6, elements common to the actuator 100 described with reference to Figure 5 are denoted by the same reference numerals and their descriptions are omitted.

[0036] The electromagnetic actuator 100A illustrated in Figure 6(a) also includes a check valve, which is an intake valve 180 and a discharge valve 190. The intake valve 180 is connected to the front part 166 of the second housing chamber 160 and draws working fluid into the second housing chamber 160. The discharge valve 190 is also connected to the front part 166 of the second housing chamber 160 and discharges working fluid from the second housing chamber 160.

[0037] According to the electromagnetic actuator 100A illustrated in Figure 6(a), the working fluid is drawn in and discharged in the space at the front of the second housing chamber 166 by reciprocating the second output shaft 150. Therefore, the sub-actuator 100b can function as a pump to deliver the working fluid, and the same effect as the electromagnetic actuator 100 can be obtained.

[0038] The electromagnetic actuator 100B illustrated in Figure 6(b) also includes a check valve, which is an intake valve 180 and a discharge valve 190. The intake valve 180 is connected to the rear 134 of the first containment chamber 130 and draws working fluid into the first containment chamber 130. The discharge valve 190 is also connected to the rear 134 of the first containment chamber 130 and discharges working fluid from the first containment chamber 130.

[0039] The electromagnetic actuator 100B, illustrated in Figure 6(b), also causes the second output shaft 150 to reciprocate, thereby drawing in and discharging the working fluid in the space at the rear 134 of the first housing chamber 130. Therefore, the sub-actuator 100b can function as a pump to deliver the working fluid, achieving the same effect as the electromagnetic actuator 100.

[0040] Preferred embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these examples. It will be obvious to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention. [Industrial applicability]

[0041] This invention can be used as an electromagnetic actuator that actively moves the shaft in both directions, achieves further miniaturization, and eliminates the need to separate the electrical circuits for driving and releasing, thereby contributing to securing mounting space for the device in a vehicle. [Explanation of symbols]

[0042] S1...First stroke, S2...Second stroke, 100, 100A, 100B...Electromagnetic actuator, 100a...Main actuator, 100b...Sub actuator, 102...Housing, 110...First coil, 120...First output shaft, 130...First housing chamber, 134...Rear, 140...Second coil, 150...Second output shaft, 160...Second housing chamber, 162...Stopper, 164...Rear, 166...Front, 180...Intake valve, 190...Discharge valve, 200...Parking lock mechanism, 210...Parking gear, 212...Teeth, 220...Parking pawl, 222...Protrusion, 230...Cam, 240...Parking rod

Claims

1. A main actuator that pushes and pulls the first output shaft, It is equipped with a sub-actuator that pushes and pulls the second output shaft, When the protruding direction of the first output shaft is forward and the retracting direction is backward, The second output shaft is positioned on the same straight line as and behind the first output shaft, An electromagnetic actuator characterized in that the first stroke of the first output shaft is greater than the second stroke of the second output shaft, and the rear of the first stroke and the front of the second stroke overlap.

2. A second housing chamber formed in the housing and accommodating the second output shaft, A suction valve connected to the rear of the second containment chamber for drawing working fluid into the second containment chamber, The system further includes a discharge valve connected to the rear of the second containment chamber for discharging working fluid from the second containment chamber, The electromagnetic actuator according to claim 1, characterized in that the working fluid is drawn in and discharged in the space at the rear of the second housing chamber by reciprocating the second output shaft.

3. A second housing chamber formed in the housing and accommodating the second output shaft, A suction valve connected to the front of the second containment chamber for drawing working fluid into the second containment chamber, The system further includes a discharge valve connected to the front of the second containment chamber for discharging working fluid from the second containment chamber, The electromagnetic actuator according to claim 1, characterized in that the working fluid is drawn in and discharged in the space in front of the second housing chamber by reciprocating the second output shaft.

4. A first housing chamber formed in the housing and accommodating the first output shaft, A suction valve connected to the rear of the first containment chamber for drawing working fluid into the first containment chamber, The system further includes a discharge valve connected to the rear of the first containment chamber for discharging working fluid from the first containment chamber, The electromagnetic actuator according to claim 1, characterized in that the working fluid is drawn in and discharged in the space at the rear of the first housing chamber by reciprocating the second output shaft.

Images