JP2011117507A - Range detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a range detecting device improving position detection accuracy by suppressing rattling during slider sliding without increasing the number of parts when horizontally installing a slide surface. <P>SOLUTION: A guide part guiding sliding of a slider body 29 has a fitting edge part 27 formed on the slider body 29, and a guide groove 37 formed on a slider rail 31 for fitting the fitting edge part 27. An edge lower face 27d of the fitting edge part 27, and a groove lower wall 37d of the guide groove 37 of the slider rail 31 contacting the edge lower face 27d are provided inclined in a direction orthogonal to a moving direction of the slider body 29 and a direction toward the fitting edge part 27 from the slider body 29. By this, rattling during sliding of a slider 21 is suppressed by an action of lateral force Fs based upon a gravity W of the slider 21 and a gradient angle θ of inclination, and since the slider 21 constantly slides on the same straight line in a sliding direction, the position detection accuracy of the range detecting device is improved. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a range detection device for an automatic transmission.

  Conventionally, as referred to in Patent Document 1, a range detection device for detecting a shift range of an automatic transmission is known. Here, the automatic transmission is mounted on a vehicle such as an automobile and includes an automatic transmission case and an oil pan. The oil pan stores hydraulic oil inside. Also, a hydraulic control device and a range detection device are accommodated in the oil pan. The range detection device detects selection of each range.

FIG. 10 shows an inhibitor switch 20 as a conventional range detection device. Here, the vertical direction in FIG. 10 indicates the actual vertical direction. That is, the inhibitor switch 20 has a slide surface installed vertically.
The inhibitor switch 20 includes a slider 71 and a slider rail 81. The slider 71 has fitting edges 75 and 76 on the upper and lower sides. The fitting edges 75 and 76 are engaged with the guide grooves 85 and 86 of the slider rail 81, respectively.

FIG. 11A shows an enlarged view of the R portion in FIG. 10, and FIG. 11B shows an enlarged view of the S portion. Due to the gravity W of the slider 71, the lower edge surface 76b contacts the groove bottom wall 86b. At this time, there are clearances between the lower side surface 76a and the inner wall 86a, between the upper side surface 75a and the inner wall 85a, and between the upper edge surface 75b and the groove bottom wall 85b.
The slider 71 slides in the front-rear direction of the drawing while the edge surface 76b and the groove bottom wall 86b are in contact with each other. That is, since the gravity W always acts downward, the clearance always exists on the upper side. Therefore, when the slider 71 is slid, “rattle” due to the clearance does not occur.

  Patent Document 2 discloses a parking range detection device that outputs or cancels a detection signal by sliding a slider with respect to a switch case. In this parking range detection device, the slider is pressed against the inner wall of the switch case by the elasticity of the spring so as not to rattle.

JP 2009-68535 A JP-A-6-191311

  By the way, depending on the restrictions on the mounting of the inhibitor switch 20, the slide surface may not be installed vertically and may be installed horizontally. In that case, since the gravity W of the slider 71 does not act on the edge surface, the position of the clearance is not fixed. Since automatic transmissions generally require high accuracy for position detection, any slight rattling when the slider 71 slides affects position detection accuracy. Therefore, when the slide surface is installed horizontally, there arises a problem that the position detection accuracy of the range detection device is lowered.

Here, a method of suppressing rattling by pressing the slider in a specific direction using a spring or a leaf spring as shown in Patent Document 2 is also conceivable, but it is possible to increase the number of parts or increase the number of assembly steps. Increases manufacturing costs.
The present invention has been made in view of the above-mentioned problems, and even when the slide surface is installed horizontally, the backlash when the slider slides is suppressed without increasing the number of parts, and the position detection accuracy is improved. An object of the present invention is to provide a range detection device that improves the above.

A range detection apparatus according to a first aspect includes a slider main body, a slider rail, a magnet, a magnetic detection element, a first guide part, and a second guide part.
The slider body can reciprocate in the horizontal direction according to the selection of the range of the automatic transmission.
The slider rail guides the slider body and slidably supports the slider body. The magnet is provided on the slider body. The magnetic detection element detects a change in magnetic force accompanying the sliding of the slider body.
The first guide portion includes a first fitting edge portion formed on one side of the slider body, and a first guide groove formed on the slider rail and into which the first fitting edge portion is fitted. The second guide portion has a second fitting edge portion formed on the other side of the slider body, and a second guide groove formed on the slider rail and into which the second fitting edge portion is fitted.
For at least one of the first guide portion and the second guide portion, the lower edge surface of the fitting edge and the groove lower wall of the guide groove in contact with the lower surface of the edge are in a direction perpendicular to the moving direction of the slider body and Inclined in the direction from the slider body toward the fitting edge.

  Thereby, a lateral force based on the gravity of the slider and the gradient angle of the inclination is generated in the direction from the fitting edge toward the slider body. Due to the action of lateral force, the slider slides down the groove lower wall and always slides on the same straight line in the sliding direction. Therefore, when the slider is pressed against the other guide groove by the lateral force, it is possible to prevent rattling from occurring when the slider slides. Therefore, the position detection accuracy of the range detection device can be improved without increasing the number of parts.

  However, when both guide portions are provided with an inclination, a lateral force acts from both sides in the sliding direction. If the balance between the left and right lateral forces is lost due to the processing dimensional accuracy of each part, or if a moment greater than the lateral force is applied, the bottom surface of one of the mating edges rides on the groove lower wall of the guide groove. The slider may tilt.

  Therefore, in the range detection device according to claim 2, for one of the first guide part and the second guide part, the edge lower surface of the fitting edge and the groove lower wall of the guide groove in contact with the lower surface of the edge are , Provided horizontally. That is, one of the guide portions is inclined and the other of the guide portions is provided horizontally. Therefore, a lateral force acts only from one side provided at an inclination to the other side provided horizontally.

Thereby, the lateral force acts only in one direction, and the slider slides while the fitting edge always contacts the guide groove on the horizontally provided guide portion side. Therefore, the rattling of the slider is suppressed even when a moment is applied, and the slider always slides on the same straight line in the sliding direction. Therefore, the position detection accuracy of the range detection device can be further improved.
Further, in the range detection device according to the second aspect, since the shapes of both guide portions are asymmetric, there is an effect in preventing erroneous assembly during the operation of assembling the slider to the slider rail.

  As described above, the range detection device of the present invention has a specific effect when the slide surface is installed horizontally. However, when the slide surface of the range detection device of the present invention is installed in the vertical direction, rattling due to the gravity of the slider can be prevented as in the prior art. Therefore, the range detection apparatus of the present invention can be used both when the slide surface is installed horizontally and when it is installed vertically.

(A): It is sectional drawing of the sliding direction of the range detection apparatus of 1st Embodiment of this invention in the state which installed the slide surface horizontally. (B): It is a bottom view of (a). (C): It is AA sectional drawing of (a), and is sectional drawing orthogonal to a sliding direction. It is a disassembled perspective view of an automatic transmission provided with the range detection apparatus of 1st Embodiment of this invention. It is the P section enlarged view of Drawing 1 (c). It is the Q section enlarged view of Drawing 1 (c). It is a characteristic view which shows the relationship between a gradient angle and a lateral force coefficient. It is the front view and partial side view which show the modification of the range detection apparatus of 1st Embodiment of this invention. It is sectional drawing of a direction orthogonal to the sliding direction of the range detection apparatus of 2nd Embodiment of this invention in the state which installed the slide surface horizontally. (A): It is sectional drawing of a direction orthogonal to the sliding direction of the range detection apparatus of a comparative example. (B): It is sectional drawing orthogonal to the sliding direction of the range detection apparatus of another comparative example. (C): It is a bottom view of (b). It is the T section enlarged view of Drawing 8 (a) and (b). It is sectional drawing of a direction orthogonal to the sliding direction of the range detection apparatus of a prior art. (a): It is the R section enlarged view of Fig.10 (a). (B): It is the S section enlarged view.

(First embodiment)
An embodiment of a range detection apparatus of the present invention will be described with reference to the drawings.
FIG. 2 shows an automatic transmission including the range detection device according to the first embodiment of the present invention. The automatic transmission includes a hydraulic control device 1 and a range detection device 2.
The hydraulic control device 1 has a hydraulic circuit including a plurality of valves such as a manual valve 5 and a plurality of flow paths. The manual valve 5 is configured by inserting a spool 7 into a spool hole 6a of the valve body 6 so as to be movable. The range of the automatic transmission is switched by switching the flow path of the hydraulic circuit according to the movement position of the spool 7. The range generally refers to each range of P, R, N, and D. P is parking, R is reverse, N is neutral, and D is drive.

The range detection device 2 includes a detent mechanism 10 and an inhibitor switch 20.
The detent mechanism 10 includes a detent plate 12, a control rod 14, a detent lever 16, an output shaft 18, and the like. The detent plate 12 and the detent lever 16 are connected by a control rod 14. When the detent lever 16 rotates around the control rod 14 as a rotation axis in response to an operation of a shift lever (not shown), the detent plate 12 rotates accordingly.
A plurality of grooves 12 a are formed on the outer edge of the detent plate 12 in the rotational direction of the detent plate 12. When the range is selected by the shift lever, one of the grooves 12a is engaged with a roller (not shown). Thereby, the rotation of the detent plate 12 is restricted when the shift lever is not operated.

  The output shaft 18 has one end fixed to the detent plate 12 and the other end engaged with the groove 7 a of the spool 7. As a result, the rotational movement of the detent plate 12 is converted into the linear movement of the spool 7, and the spool 7 slides in the axial direction in accordance with the operation of the shift lever.

The inhibitor switch 20 includes a slider 21 and a slider rail 31. The slider rail 31 is fixed to the valve body 6 and has a slide surface on which the slider 21 slides. The slider rail 31 includes a hall element 43 on the back side of the slide surface.
The input shaft 22 of the slider 21 is engaged with the groove 7 b of the spool 7. Therefore, the slider 21 slides along the slide surface of the slider rail 31 following the sliding of the spool 7. Therefore, the slider 21 moves to a position corresponding to the selection of each range. Further, since the rotation of the detent plate 12 is restricted when the shift lever is not operated, the movement of the slider 21 is restricted at a position corresponding to the selection of each range.

FIG. 1 is a diagram showing an inhibitor switch 20. The vertical direction in FIGS. 1A and 1C indicates the actual vertical direction.
The slider rail 31 is installed horizontally and has a slide chamber 32 below the base portion 33. Guide grooves 35 and 37 are formed on both sides of the slide chamber 32 in the longitudinal direction. The upper surface of the slide chamber 32 forms a slide surface 33a.
Fitting edges 25 and 27 are formed on both sides of the slider body 29. The fitting edges 25 and 27 are fitted in the guide grooves 35 and 37, respectively. The guide portion 34p has a fitting edge portion 27 and a guide groove 37, and the guide portion 34q has a fitting edge portion 25 and a guide groove 35. The slider 21 is guided by both guide portions 34p and 34q, and slides in the sliding direction Sx along the slide surface 33a. An input shaft 22 is provided on the slider lower surface 24. The input shaft 22 receives a driving force from the spool 7 of the manual valve 5 according to the selection of the range.

  A substrate accommodating chamber 42 surrounded by an outer wall 41 is formed on the upper side of the base portion 33 of the slider rail 31. In the substrate housing chamber 42, an electrical element 44 such as a capacitor and a resistor, and a circuit board 45 are accommodated in addition to the Hall element 43 as a magnetic detection element. The circuit board 45 is wired by a wire harness 46.

  The slider 21 has a magnet inside or is magnetized to generate a magnetic force. Further, since the slider 21 is preferably made of a light and lubricious material in order to reduce friction during sliding, it is made of, for example, a plastic magnet.

  The Hall element 43 is an element that detects a magnetic field using the Hall effect, and embodies the “magnetic detection element” described in “Claims”. The Hall element 43 detects a change in magnetic force that occurs as the slider 21 slides, and outputs a detection signal. In order to increase the detection accuracy, a plurality of Hall elements 43 are used. Although FIG. 2 illustrates an example in which the two Hall elements 43 are arranged in the orthogonal direction of the sliding direction Sx, the present invention is not limited to this, and three or more elements can be used. Further, a magnetoresistive element or the like may be used as the magnetic detection element.

  The detection signal output from the Hall element 43 is A / D converted from, for example, an analog signal to a digital signal by a detection circuit, and the range selected by the shift lever is detected by recognizing the magnetic field pattern.

FIG. 3 is an enlarged view of a portion P in FIG. 1C and shows one guide portion 34p. FIG. 4 is an enlarged view of the Q portion and shows the other guide portion 34q. Hereinafter, the P portion is referred to as “inclined side” and the Q portion is referred to as “horizontal side”.
On the “inclined side”, the lower surface of the fitting edge of the slider 21 and the groove lower wall of the guide groove of the slider rail 31 are provided to be inclined so that the outer side becomes higher. Therefore, the names of the respective parts are expressed as “lower edge inclined surface 27 d of the inclined fitting edge portion 27 of the slider 21” and “lower groove inclined wall 37 d of the inclined guide groove 37 of the slider rail 31”.
On the other hand, on the “horizontal side”, the same part is provided horizontally. Therefore, the names of the respective parts are expressed as “the lower edge surface 25d of the horizontal fitting edge 25 of the slider 21” and “the groove lower wall 35d of the horizontal guide groove 35 of the slider rail 31”.

  As shown in FIG. 3, the inclined fitting edge portion 27 of the slider 21 includes a side surface 27a, an edge end surface 27b, an edge upper surface 27c, and a lower edge inclined surface 27d. Further, the inclined guide groove 37 of the slider rail 31 includes an inner wall 37a, a groove bottom wall 37b, a groove upper wall 37c, and a groove lower inclined wall 37d. The lower edge inclined surface 27d is in contact with the lower groove inclined wall 37d by gravity W. A clearance is provided between the edge upper surface 27c and the groove upper wall 37c. In addition, the dimensions of each part are set so that a clearance is generated between the edge surface 27b and the groove bottom wall 37b and between the side surface 25a and the inner wall 35a. These clearances are indispensable for the slider 21 to slide smoothly.

The gravitational force W of the slider 21 is represented by the product of the mass m of the slider 21 and the gravitational acceleration g as shown in Equation 1.
W = mg (Formula 1)
The gradient angle θ is an angle in the range of Equation 2.
0 ° <θ <90 ° (Formula 2)

The forces acting on the contact surface between the lower edge inclined surface 27d and the lower groove inclined wall 37d with the gradient angle θ are expressed by Equations 3 to 6. Fc is a force in the vertical direction, Fa is a component force of Fc in the direction along the inclined surface, and Fb is a component force of Fc in the direction perpendicular to the inclined surface. Fs is a component force of Fa in the horizontal direction, and is referred to as “lateral force”. In this case, the lateral force Fs acts from the outside of the slider 21 toward the inside. Therefore, as will be described later, the slider 21 slides down the groove lower inclined wall 37d until the edge surface 25b hits the groove bottom wall 35b in the horizontal guide portion 34q.
Fc = W (Formula 3)
Fa = Wsinθ (Formula 4)
Fb = W cos θ (Formula 5)
Fs = Wsin θ · cos θ (Expression 6)

  As shown in FIG. 4, the horizontal fitting edge portion 25 of the slider 21 includes a side surface 25a, an edge surface 25b, an edge upper surface 25c, and an edge lower surface 25d. Further, the horizontal guide groove 35 of the slider rail 31 includes an inner wall 35a, a groove bottom wall 35b, a groove upper wall 35c, and a groove lower wall 35d. The lower edge surface 25d is in contact with the groove lower wall 35d by gravity W. A clearance is provided between the edge upper surface 25c and the groove upper wall 35c. In the present embodiment, the edge surface 25b is pressed against and contacts the groove bottom wall 35b by the lateral force Fs. Since the length of the horizontal fitting edge 25 in the fitting direction is set larger than the depth of the horizontal guide groove 35, there is a clearance between the side surface 25a and the inner wall 35a.

  Further, an upper surface clearance Cu is provided between the slider upper surface 23 and the slide surface 33a of the slider rail 31 in common to both the guide portions 34p and 34q. Since the upper surface clearance Cu determines the distance between the magnet in the slider 21 and the Hall element 43 and affects the detection accuracy, it is desirable to be as constant as possible.

  FIG. 5 shows the relationship between the gradient angle θ and the lateral force coefficient sin θ · cos θ. When the gradient angle θ is 0 ° and 90 °, the lateral force coefficient sin θ · cos θ is 0, and when the gradient angle θ is 45 °, the lateral force coefficient sin θ · cos θ is 0.5. The gradient angle θ increases as the angle increases from 0 ° to 45 °, and decreases as the angle increases from 45 ° to 90 °. Therefore, if the effect of the lateral force Fs is to be utilized to the maximum, it can be said that the gradient angle θ is preferably about 45 °.

However, from another viewpoint, when the gradient angle θ is large, the change in the upper surface clearance Cu when the slider 21 slides down the groove lower inclined wall 37d becomes large. That is, in the movement from the initial position of the slider 21 until the edge surface 25b hits the groove bottom wall 35b in the horizontal guide portion 34q, the upper surface clearance Cu is widened. For this reason, the distance between the magnet in the slider 21 and the Hall element 43 is increased, resulting in a decrease in detection accuracy.
In order to prevent this, it is necessary to make the dimensional accuracy of the clearance and angle associated with the slider 21 and the slider rail 31 very strict, which is not practical in manufacturing. Therefore, it is better to decrease the gradient angle θ.

Therefore, it can be said that there is no merit in setting the gradient angle θ to be larger than 45 °. Therefore, Equation 2 may be replaced as Equation 2 ′.
0 ° <θ ≦ 45 ° (Formula 2 ')
Therefore, it is desirable to study the balance between the effect of the lateral force Fs and the accuracy of the upper surface clearance Cu within the range of the formula 2 ′, and to design an appropriate gradient angle θ in consideration of the manufacturing situation.

  Thus, in this embodiment, the lateral force Fs acts only in one direction, and the edge surface 25b slides in contact with the groove bottom wall 35b of the slider rail 31 in the guide portion 34q of the slider 21. Therefore, rattling of the slider 21 is suppressed even when a moment is applied, and the slider 21 always slides on the same straight line in the sliding direction Sx. Moreover, in this embodiment, components, such as a spring, are not required. Therefore, the position detection accuracy of the range detection device can be improved without increasing the number of parts.

  Furthermore, when both guide portions are provided symmetrically, there is a possibility that the slider 21 is assembled in the reverse direction during the operation of assembling the slider rail 31. In this embodiment, the one guide portion 34p is inclined. Accordingly, the shapes of the guide portions 34p and 34q are asymmetrical, which is effective in preventing erroneous assembly.

(Modification of the first embodiment)
FIG. 6 shows a modification of the first embodiment. In this modification, the lower edge inclined surface 27d is provided intermittently in the axial direction of the slider 21, and a relief portion is provided between the adjacent lower edge inclined surfaces 27d. Thus, the inclined edge lower surface 27d or the horizontal edge lower surface 25d may not be provided over the entire region in the axial direction. If the contact area necessary for receiving the load during sliding of the slider 21 can be secured, the contact resistance can be reduced by providing the relief portion.

(Comparative example)
Here, the case where the inhibitor switch 20 in which both guide portions are provided horizontally is installed horizontally will be described as a comparative example. In addition, in order to distinguish from this invention, in a comparative example, it represents using the code | symbol of "the slider 71, the input shaft 72, the slider rail 81".
FIG. 8A is a comparative example in which the input shaft 72 is provided on the center of gravity of the slider 71. FIG. 8B is a diagram in which the input shaft 72 is ΔX in the sliding direction Sx from the center of gravity Og of the slider 71. This is a comparative example in the case of being provided with an offset of ΔY in the orthogonal direction.
FIG. 9 is an enlarged view of a T portion in FIGS. 8 (a) and 8 (b). As shown in FIG. 9, the lower edge surface 75 d comes into contact with the groove lower wall 85 d due to the gravity W of the slider 71. The same applies to the T ′ portion on the opposite side.

  Since a force in a fixed direction does not act on the slider 71 in the left-right direction in the figure, the slider 71 can move in any direction as shown by a double-point broken line arrow in FIG. 9 due to impact or vibration. That is, it is not determined whether or not the edge surface 75b and the groove bottom wall 85b are in contact with each other at the T portion and the T ′ portion. Therefore, in the case where the input shaft 72 is provided on the center of gravity and in the case where the input shaft 72 is provided with an offset, there is a possibility that rattling occurs when the slider 71 slides. In particular, when the input shaft 72 is provided with an offset, the moment M acts around the center of gravity Og when the input shaft 72 receives the driving force Fi as shown in FIG. A rattling occurs.

(Second Embodiment)
As shown in FIG. 7, the range detection apparatus of the present invention can be provided with both guide portions inclined. In this case, if both the guide portions 34 have the same gradient angle θ, and the lower edge inclined surface 27d and the lower groove inclined wall 37d are formed at symmetrical positions with respect to the central axis, the lateral force Fs is theoretically determined from the left and right. Take evenly. Therefore, it is considered that the slider 21 slides on the same straight line in the sliding direction Sx so that the center of gravity of the slider 21 is along the central axis of the slider rail 31.

However, in reality, if the balance between the left and right lateral forces Fs is lost due to the processing dimensional accuracy of each part, or if a moment greater than the lateral force Fs is applied, one of the lower inclined surfaces 27d is inclined below the groove There is a possibility that the slider 21 tilts after riding on 37d. Therefore, it is considered that the first embodiment is more suitable for realization.
However, in the second embodiment as well, when the slide surface is installed horizontally, rattling of the slider 21 is prevented compared to the prior art, and the position detection of the range detection device is performed without increasing the number of parts. Accuracy can be improved.

  As described above, the range detection device of the present invention has a specific effect when the slide surface is installed horizontally. However, when the slide surface of the range detection device of the present invention is installed in the vertical direction, rattling due to the gravity W of the slider 21 can be prevented as in the prior art. Therefore, the range detection apparatus of the present invention can be used both when the slide surface is installed horizontally and when it is installed vertically.

  As mentioned above, this invention is not limited to such embodiment, In the range which does not deviate from the meaning of invention, it can implement with a various form.

  1: hydraulic control device, 2: range detection device, 5: manual valve, 6: valve body, 6a: spool hole, 7: spool, 10: detent mechanism, 20: inhibitor switch, 21: slider, 22: input shaft, 23: Slider upper surface, 25: Horizontal fitting edge, 25d: Edge lower surface, 27: Inclined fitting edge, 27d: Lower edge inclined surface, 29: Slider body, 31: Slider rail, 32: Slide chamber, 33: Base part, 33a: slide surface, 34, 34p, 34q: guide part, 35: horizontal guide groove, 35d: groove lower wall, 37: inclined guide groove, 37d: lower groove inclined wall, 41: outer wall, 42: substrate accommodation Chamber 43, Hall element (magnetic detection element) 45: Circuit board, Cu: Upper surface clearance, Fs: Lateral force, Sx: Sliding direction, W: Gravity, θ: Gradient angle

Claims (2)

According to the selection of the range of the automatic transmission, a slider body that can reciprocate horizontally,
A slider rail that guides the slider body and slidably supports the slider body;
A magnet provided in the slider body;
A magnetic detection element that is provided on the slider rail and detects a change in magnetic force caused by sliding of the slider body;
A first guide portion having a first fitting edge portion formed on one side of the slider body, and a first guide groove formed on the slider rail and into which the first fitting edge portion is fitted; ,
A second guide portion having a second fitting edge portion formed on the other side of the slider body, and a second guide groove formed on the slider rail and into which the second fitting edge portion is fitted; With
About at least one of the first guide part and the second guide part,
The lower surface of the edge of the fitting edge and the groove lower wall of the guide groove in contact with the lower surface of the edge are in a direction orthogonal to the moving direction of the slider body and in a direction from the slider body to the fitting edge. A range detection apparatus provided with an inclination. About one of the first guide part and the second guide part,
The range detection device according to claim 1, wherein a lower surface of the edge of the fitting edge and a groove lower wall of the guide groove in contact with the lower surface of the edge are provided horizontally.

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