JPH0592629U - Rotation detector - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide a rotation detecting device capable of smoothly supporting a shaft member by a bearing member without utilizing lubricating oil in an object to be measured. [Structure] A shaft member 15 for transmitting the rotational motion of a rotating body (gear) provided on an object to be measured (engine) to the rotation detecting means 30 side, and a bearing member 11a for rotatably holding the shaft member 15 are provided. In the rotation detecting device, the shaft member 15 has a grease reservoir 18 having a hollow interior, and a grease supply hole 19 leading from the grease reservoir to the outer peripheral surface.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rotation detecting device for detecting the number of rotations of a rotating body such as an output shaft of an engine.

[0002]

[Prior Art]

 As a conventional rotation detection device of this type, for example, a device shown in FIG. 7 is known as a device for detecting the rotation speed of an engine (object to be measured). That is, the housing 1 is attached to a mission case of an engine (not shown), and an O-ring 2 for preventing leakage of lubricating oil in the mission is provided on the outer peripheral portion of the housing 1. A transmission shaft (shaft member) 3 is rotatably provided inside the housing 1, and a driven gear 4 that meshes with a gear (rotating body) in a mission is attached to a tip end portion of the transmission shaft 3. ..

The transmission shaft 3 has a spiral oil groove 5 formed on the outer circumference, and lubricates the outer peripheral surface by introducing lubricating oil in the mission. Further, a coupling portion 6 is formed at the base end portion of the transmission member 3, and a drive shaft 8 that rotationally drives the magnetic rotor 7 is connected to the coupling portion 6. The end surface 7a of the magnetic rotor 7 is magnetized in multiple poles, and the magnetic sensitive element 9 is provided so as to be close to the end surface 7a. The magnetic rotor 7 and the magnetically sensitive element 9 constitute the rotation detecting means 10.

[0004]

[Problems to be solved by the device]

 However, in the above-described conventional rotation detecting device, the outer peripheral surface of the transmission shaft 3 is lubricated by utilizing the lubricating oil in the mission, so that the lubricating oil in the transmission shaft 3 is sufficiently intruded so that the transmission shaft 3 is mounted on the mission. The location had to be considered, and there was a problem that the installation was troublesome. Then, there is a problem that it cannot be attached to a measurement object that does not use lubricating oil.

The present invention has been made in order to solve the above-mentioned problem, and its purpose is to detect rotation in which a shaft member can be smoothly supported by a bearing member without using lubricating oil in an object to be measured. To provide a device.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the invention of claim 1 provides a shaft member for transmitting the rotational movement of a rotating body provided on an object to be measured to a rotation detecting means side, and a bearing member for rotatably holding the shaft member. And a shaft member having a grease reservoir having a hollow interior and a grease supply hole communicating from the grease reservoir to the outer peripheral surface. It has a feature.

Further, the invention of claim 2 is provided with a shaft member for transmitting the rotational movement of the rotating body provided on the object to be measured to the rotation detecting means side, and a bearing member for rotatably holding the shaft member. The rotation detecting device is characterized in that the shaft member is made of resin.

Further, the invention of claim 3 is characterized in that the shaft member of claim 2 is formed as follows. That is, the shaft member is formed so as to have a grease reservoir having a hollow inside and a grease supply hole communicating from the grease reservoir to the outer peripheral surface.

Furthermore, the invention of claim 4 is characterized in that a groove extending in the axial direction is formed on the outer peripheral surface of the shaft member according to any one of claims 1 to 3.

Further, the invention of claim 5 is characterized in that a groove along the axial direction is formed on the outer peripheral surface of the shaft member of claim 1 or 3, and the grease supply hole is passed through this groove. There is.

Further, the invention according to claim 6 is characterized in that a spiral groove is formed on the outer peripheral surface of the shaft member according to any one of claims 1 to 3.

Further, the invention of claim 7 is characterized in that a spiral groove is formed on the surface of the shaft member of claim 1 or 3, and the grease supply hole is passed through this groove. There is.

[0013]

[Action]

 In the invention of claim 1 configured as described above, the grease in the grease reservoir gradually flows from the grease supply hole to the outer peripheral surface of the shaft member, and the lubrication between the shaft member and the bearing member is maintained for a long period of time. Be done. For this reason, the shaft member can be smoothly supported by the bearing member without using the lubricating oil provided inside the measurement object, and the rotation can be detected by mounting the shaft member at a free position on the measurement object. be able to.

Further, in the invention of claim 2, since the shaft member is made of resin, the coefficient of friction of the shaft member with respect to the bearing member becomes extremely small. Therefore, also in this case, the shaft member can be smoothly supported by the bearing member without using the lubricating oil in the measurement object.

Further, in the invention of claim 3, since the shaft member is made of resin and has the grease reservoir and the grease supply hole, the shaft member can be supported more smoothly.

Further, in the invention of claim 4, since the groove along the axial direction is formed on the outer peripheral surface of the shaft member, the shaft member is formed of a material having a larger thermal expansion coefficient than the bearing member. Also, the circumferential expansion component of the shaft member can be absorbed by the groove to prevent the circumferential expansion component from becoming the radial expansion component. Therefore, it is not necessary to take a large gap between the shaft member and the bearing member in consideration of thermal expansion, and the gap between the shaft member and the bearing member can be made small, so that the shaft member is smoothly supported by the bearing member. can do. Furthermore, since the heat dissipation area of the outer peripheral surface of the shaft member is increased by the groove, the temperature rise of the shaft member can be suppressed, and from this point as well, the gap between the shaft member and the bearing member can be reduced. In addition, since the temperature of the shaft member can be kept low, deterioration of the shaft member can be reduced.

Further, in the invention of claim 5, since the grease is supplied to the groove, the grease can be evenly supplied to the entire outer peripheral surface of the shaft member. The invention of claim 6 has the same operation as that of claim 4, and the invention of claim 7 has the same effect as that of claim 5.

[0018]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS.

First, a first embodiment of the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 11 denotes a housing that can be attached to an object to be measured, for example, an engine mission (not shown). The outer peripheral portion of the housing 11 is lubricated from the inside of a mission or the like. An O-ring 12 is provided to prevent oil from leaking. The housing 11 is formed by aluminum die-casting, and a bearing hole (bearing member) 11a having a circular cross section for holding a transmission shaft (shaft member) 15 to be described later is provided at the center of the shaft from the tip side. It is formed toward the end side. The bearing hole 11a is precisely finished in terms of roundness, straightness, surface roughness of the inner surface, etc. by machining or the like, and the rotary motion take-out member 13 is inserted into the bearing hole 11a from the tip side. ing.

As shown in FIG. 2, the rotary motion take-out member 13 is formed by coaxially molding a driven gear 14 and a transmission shaft 15 with a resin such as nylon or polyphenylene sulfide. The driven gear 14 is adapted to mesh with a gear (rotating body) in a transmission (not shown), and the transmission shaft 15 is divided into a distal end portion 15a and a proximal end portion 15b by an annular groove 16 formed on the outer circumference. Spiral grooves 17 are formed on the outer circumferences of the distal end portion 15a and the proximal end portion 15b, respectively, and a grease reservoir 18 is formed at the axial center of the proximal end portion 15b.

The grease reservoir 18 is formed in a hollow hole shape having a circular cross section so as to reach the annular groove 16 from the base end surface of the base end portion 15b. From the grease reservoir 18 to the spiral groove 17 in the outer peripheral portion. A plurality of grease supply holes 19 are formed so as to penetrate therethrough. The grease supply hole 19 is formed to have a diameter of about 0.1 mm to 2 mm, and the diameter of the grease supply hole 19 is determined so that the grease in the grease reservoir 18 does not overflow to the spiral groove 17 and does not become insufficient. There is.

A coupling portion 20 is formed on the base end side of the base end portion 15b. The coupling portion 20 has a pair of grooves 21 extending from the base end surface of the base end portion 15b to the tip side, and the drive shaft (rotatingly driving the magnetic rotor 22 so as to engage with the grooves 21). Shaft member) 23 is connected. As shown in FIG. 3, the magnetic rotor 22 is a disk-shaped one whose end face 22a is magnetized in multiple poles. The drive shaft 23 has a base end fixed coaxially to the shaft center of the magnetic rotor 22 and is formed by inserting the magnetic rotor 22 with a resin such as nylon or polyphenylene sulfide. Further, the drive shaft 23 is rotatably supported by a slide bearing (bearing member) 24 at a portion near the magnetic rotor 22.

Further, the drive shaft 23 is provided with a grease reservoir 25 in the shape of a hollow so as to penetrate the portion of the slide bearing 24 from the tip side, and the slide bearing 24 is fitted from the grease reservoir 25. A plurality of grease supply holes 26 are formed so as to penetrate the outer peripheral surface of the portion to be filled. The grease supply hole 26 is formed to have a diameter of about 0.1 mm to 2 mm, and the diameter thereof is determined so that the grease in the grease reservoir 25 does not overflow or run short on the outer peripheral surface. .. A key 27 that engages with the groove 21 of the coupling portion 20 of the transmission shaft 15 is provided on the outer periphery of the tip of the drive shaft 23.

A through hole 11b formed continuously with the bearing hole 11a is opened at the base end portion of the housing 11, and an end cap 28 is fixed so as to close the opening portion. A magnetic sensitive element 29 is provided on the end cap 28 so as to be close to the end surface 22 a of the magnetic rotor 22. The magnetic rotor 22 and the magnetically sensitive element 29 constitute a rotation detecting means 30.

The magnetic sensitive element 29 is composed of a Hall element or the like, and is adapted to emit an electric signal in accordance with the number of rotations of the magnetic rotor 22, and electrically connected to a terminal 31 provided on the end cap 29. It is connected to the. The terminal 31 is connected to an indicator (not shown) or the like so as to send an electric signal generated by the magnetic sensitive element 29 to the indicator or the like.

Further, in FIG. 1, reference numeral 32 is a retaining member of the transmission shaft 15, and the retaining member 32 has a cylindrical outer peripheral surface having a shape fitted in the annular groove 16 of the transmission shaft. It is provided so as to penetrate from the outside of the housing 11 through the annular groove 16 of the transmission shaft 15.

In the rotation detecting device configured as described above, the grease reservoirs 18 and 25 are filled with grease, and the outer peripheral surfaces of the transmission shaft 15 and the drive shaft 23 are thinly coated with these greases. The transmission shaft 15 and the drive shaft 23 are assembled in the housing 11. Then, the rotation detection device thus assembled is attached to the mission.

When the engine is started in this state, the rotational movement of the gears in the mission is taken out via the driven gear 14 and further transmitted to the magnetic rotor 22 via the transmission shaft 15 and the drive shaft 23. Then, the magnetic sensitive element 29 outputs an electric signal corresponding to the number of revolutions of the magnetic rotor 22 to an indicating instrument or the like.

In the initial stage, the transmission shaft 15 and the drive shaft 23 are sufficiently lubricated by the grease applied first. Then, as the use period elapses, the grease applied to the outer peripheral surface is gradually consumed, and the pressure of the grease on the outer peripheral surface gradually decreases. Then, the pressure of the grease that flows out from the grease reservoirs 18 and 25 to the outside by centrifugal force becomes larger than the pressure of the grease on the outer peripheral surface, and the grease passes through the grease supply holes 19 and 26 and spirals. It gradually comes out to the groove 17 or the outer peripheral surface. In this way, the lubrication of the transmission shaft 15 and the drive shaft 23 is stably maintained for a long period of time.

According to the rotation detecting device configured as described above, the lubrication of the transmission shaft 15 and the drive shaft 23 can be stably maintained for a long period of time by the grease in the grease reservoirs 18 and 25. For example, the transmission shaft 15 and the drive shaft 23 can be lubricated without using the lubricating oil in the transmission of the engine, which is the object. Therefore, the lubricant can be mounted at any position on the mission without being restricted by the position of the lubricating oil in the mission, and the trouble of designing the mounting position can be eliminated.

Moreover, by installing the transmission in a portion where the lubricating oil does not exist, it is possible to reliably prevent the leakage of the lubricating oil from the mounting portion of the housing 11. Furthermore, it has a remarkable effect that it can be attached to an object to be measured which does not have lubricating oil.

In the above embodiment, the grease supply holes 19 are formed by arranging three grease supply holes in one direction as shown in FIG. 2, but the grease supply holes 19 are different in the circumferential direction. It goes without saying that a plurality may be provided at the position. Further, it is preferable to provide a plurality of pairs of grease supply holes 19 and arrange the pairs of grease supply holes at positions separated by 180 degrees in the circumferential direction in order to supply all the grease inside by centrifugal force. Similarly, it is preferable that the grease supply hole 26 of the drive shaft 23 is also provided at a position separated by 180 degrees in the circumferential direction.

Further, although the grease reservoir 18 is formed only in the base end portion 15b, it is formed so as to penetrate both the base end portion 15b and the tip end portion 15a, and the spiral groove 17 on the side of the tip end portion 15a from the grease reservoir 18 is formed. The grease supply hole 19 may be formed so as to communicate with the above. Further, the grease supply hole 19 may be formed so as to communicate with the annular groove 16 from the grease reservoir 18. A spiral groove is not formed in the slide bearing 24 portion of the drive shaft 23, but a spiral groove 17 similar to the transmission shaft 15 is formed in this portion as well, and a grease supply hole 26 communicating with the spiral groove 17 is formed. May be formed.

Further, although the transmission shaft 15 and the driven gear 14 are integrally formed, it goes without saying that they may be separately formed. Moreover, although the transmission shaft 15, the driven gear 14, and the drive shaft 23 are formed of resin to improve lubricity, it goes without saying that they may be formed of other materials such as metal.

Furthermore, the transmission shaft 15 and the drive shaft 23 may be improved in lubricity only by being formed of resin. That is, the transmission shaft 15 and the drive shaft 23 may be made of resin, and the grease reservoir 18, grease supply hole 19, spiral groove 17, and other grease storage and supply means may not be provided.

Next, a second embodiment of the present invention will be described with reference to FIGS. However, the elements common to the first embodiment shown in FIGS. 1 to 3 are given the same reference numerals, and the description thereof will be omitted.

That is, the housing 41 is adapted to be attached to a measurement object, such as an engine mission (not shown), via a female screw portion 41a formed on the inner peripheral surface on the front end side. An introduction hole 41b of a transmission shaft (shaft member) 42 formed coaxially with the female screw portion 41a is formed on the base end side of the portion 41a. Further, a through hole 41c continuous with the introduction hole 41b is opened at the base end portion of the housing 41, and the end cap 28 is fixed so as to close the through hole 41c.

The transmission shaft 42 transmits the rotational movement of the rotating body in the mission (not shown) to the drive shaft (shuffle member) 43, and the key 42a is formed on the outer circumference of the tip end portion. The key 42a is a part of the transmission shaft 42 raised by a press or the like, and is fitted in a key groove (not shown) formed in the rotating body in the mission. Further, the base end portion of the transmission shaft 42 is a joint portion 42b having a square cross section.

The drive shaft 43 is made of a resin such as nylon or polyphenylene sulfide, and its shaft center has a joint hole with a square cross section into which the joint portion 42b of the transmission shaft 42 fits from the tip side. The part 43a is formed. The magnetic rotor 22 is coaxially fixed to the base end of the drive shaft 43. Further, the drive shaft 43 has a sliding surface (outer peripheral surface) 43 b in which a portion near the magnetic rotor 22 is rotatably fitted to the slide bearing 24.

As shown in FIG. 5, a plurality of linear grooves 43c extending parallel to the axial direction are formed on the sliding surface 43b. As shown in FIG. 6, the linear groove 43c has a bottom surface 43d formed by an arcuate surface centered on the axis, and side surfaces 43e, 43e adjacent to the bottom surface 43d face in a radial direction from the axis. Formed by the surface. The straight grooves 43c are formed at equal intervals in the circumferential direction, and the dimension A of the outer circumferential surface between the adjacent straight grooves 43c and the dimension B of the bottom surface 43d in the circumferential direction are expressed by the following equation (1). It is formed in.

B ≦ A ≦ 2B (1) Further, the dimension B and the dimension D of the side surface 43e in the depth direction are formed to be substantially equal to each other.

As shown in the above equation (1), the dimension A is formed to be equal to or larger than the dimension B because when the dimension A 2 is smaller than the dimension B, the area where the sliding surface 43 b contacts the sliding bearing 24 is small. This is because the surface pressure of the sliding surface 43b becomes too large, and the dimension A is formed to be twice the dimension B 2 or less for the following reason. That is, when the temperature of the drive shaft 43 rises, the component that expands in the circumferential direction becomes a component that expands in the radial direction when the linear groove 43c is not provided, which causes an increase in diameter. When the groove 43c is provided, the expansion component in the circumferential direction is absorbed by the linear groove 43c, and the expansion component in the circumferential direction is prevented from becoming the expansion component in the radial direction. However, if the dimension A is larger than twice the dimension B 1, it becomes difficult to absorb the expansion component in the circumferential direction by the linear groove 43c, and the diameter of the drive shaft 43 increases.

Further, the dimension B and the dimension D are formed to be substantially equal to each other. When the dimension D becomes smaller than the dimension B, the linear groove 43c is shallow, and therefore the expansion component in the circumferential direction is generated by the linear groove 43c. This is because, when the dimension D becomes larger than the dimension B, the linear groove 43c becomes deep and the strength of the convex portion of the sliding surface 43b decreases.

According to the rotation detector configured as described above, when the slide bearing 24 is made of metal, the thermal expansion coefficient of the drive shaft 43 made of resin is larger than that of the slide bearing 24. Since it is larger than the coefficient, it is necessary to take a large gap between the slide bearing 24 and the drive shaft 43 in consideration of thermal expansion, but a plurality of linear grooves 43 c are formed on the sliding surface 43 b of the drive shaft 43. Therefore, it is possible to absorb the expansion component in the circumferential direction of the drive shaft 43 by the linear groove 43c and prevent this expansion component in the circumferential direction from becoming the expansion component in the radial direction. The gap between the plain bearing 24 and the drive shaft 43 can be made smaller than in the case where there is no such bearing.

Therefore, it is possible to reduce the play between the slide bearing 24 and the drive shaft 43, which can improve the life of the drive shaft 43 and can endure higher speed rotation. .. Further, since the heat dissipation area of the sliding surface 43b is increased by the linear groove 43c, the temperature rise of the drive shaft 43 can be suppressed, and from this point also, the gap between the slide bearing 24 and the drive shaft 43 can be reduced. Can Moreover, since the temperature of the drive shaft 43 can be kept low, deterioration of the drive shaft 43 can be reduced.

Although the linear groove 43c is formed on the sliding surface 43b of the drive shaft 43 in the second embodiment, the spiral groove 17 shown in the first embodiment is used instead of the linear groove 43c. It may be formed. Further, the grease reservoir 25 and the grease supply hole 26 similar to those in the first embodiment may be provided in the drive shaft 43. In this case, it is preferable that the grease supply hole 26 communicates with the linear groove 43c. Further, it goes without saying that the linear groove 43c may be formed on the sliding surfaces of the transmission shaft 15 and the drive shaft 23 of the first embodiment.

[0047]

[Effect of the device]

 According to the first aspect of the present invention, the grease gradually flowing from the grease supply hole to the outer peripheral surface of the shaft member can stably maintain the lubrication between the shaft member and the bearing member for a long period of time. The rotation can be detected by mounting it on an object that does not exist. Therefore, the shaft member can be smoothly supported by the bearing member without using the lubricating oil in the measurement object.

According to the invention of claim 2, since the shaft member is made of resin, the coefficient of friction of the shaft member with respect to the bearing member can be made extremely small. Therefore, also in this case, the shaft member can be smoothly supported by the bearing member without using the lubricating oil in the measurement object.

Further, in the invention of claim 3, since the shaft member is made of resin, and the grease reservoir and the grease supply hole for supplying the grease to the outer peripheral surface of the bearing member are provided, The shaft member can be supported more smoothly.

Further, in the invention of claim 4, since the groove along the axial direction is formed on the outer peripheral surface of the shaft member, the shaft member is made of a material having a large thermal expansion coefficient with respect to the bearing member. Even if it is, the circumferential expansion component of the shaft member can be absorbed by the groove, and the circumferential expansion component can be prevented from becoming the radial expansion component. Therefore, in consideration of thermal expansion, it is not necessary to make a large gap between the shaft member and the bearing member, that is, the gap between the shaft member and the bearing member can be made small. Can be supported. Further, since the groove increases the heat radiation area on the outer peripheral surface of the shaft member, the temperature rise of the shaft member can be suppressed. From this point as well, the gap between the shaft member and the bearing member can be reduced, and the shaft The member can be smoothly supported. In addition, since the temperature of the shaft member can be kept low, deterioration of the shaft member can be reduced.

Further, in the invention of claim 5, since the grease is supplied to the groove, the grease can be evenly supplied to the entire outer peripheral surface of the shaft member. Further, in the invention of claim 6, the same operational effect as that of the above-mentioned claim 4 is exhibited, and in the invention of claim 7, the same operational effect as that of the above-mentioned claim 5 is exhibited.

[Brief description of drawings]

FIG. 1 is a sectional view of a rotation detecting device shown as a first embodiment of the present invention.

FIG. 2 is a sectional view showing a transmission shaft and a driven gear of the rotation detection device.

FIG. 3 is a cross-sectional view showing a drive shaft of the rotation detection device.

FIG. 4 is a sectional view of a rotation detecting device shown as a second embodiment of the present invention.

FIG. 5 is a cross-sectional perspective view of a main part showing a drive shaft of the rotation detection device.

FIG. 6 is an enlarged view of a VI portion of FIG.

FIG. 7 is a sectional view of a rotation detecting device shown as a conventional example.

[Explanation of symbols]

 11a Bearing member (bearing hole) 15 Shaft member (transmission shaft) 17 Spiral groove 18 Grease reservoir 19 Grease supply hole 23 Shaft member (drive shaft) 24 Bearing member (sliding bearing) 25 Grease reservoir 26 Grease supply hole 30 Rotation detecting means 42 Shaft member (transmission shaft) 43 Shaft member (drive shaft) 43b Sliding surface (outer peripheral surface) 43c Groove along the axial direction (straight groove)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G01P 3/487 B 9010-2F // F02D 35/00 362 G 9038-3G

Claims (7)

[Scope of utility model registration request] 1. A rotation detecting device comprising a shaft member for transmitting a rotational movement of a rotating body provided on an object to be measured to a rotation detecting means side, and a bearing member rotatably holding the shaft member, The rotation detecting device, wherein the shaft member has a grease reservoir having a hollow interior and a grease supply hole communicating from the grease reservoir to the outer peripheral surface. 2. A rotation detecting device comprising a shaft member for transmitting a rotational movement of a rotating body provided on an object to be measured to a rotation detecting means side, and a bearing member for rotatably holding the shaft member, The rotation detecting device, wherein the shaft member is made of resin. 3. The shaft member has a grease reservoir having a hollow interior, and a grease supply hole communicating from the grease reservoir to an outer peripheral surface of the shaft member. Rotation detection device. 4. The rotation detecting device according to claim 1, wherein a groove along the axial direction is formed on the outer peripheral surface of the shaft member. 5. The rotation detecting device according to claim 1, wherein a groove along the axial direction is formed on the outer peripheral surface of the shaft member, and the grease supply hole communicates with the groove. apparatus. 6. The rotation detecting device according to claim 1, wherein a spiral groove is formed on the outer peripheral surface of the shaft member. 7. The rotation detecting device according to claim 1 or 3, wherein a spiral groove is formed on the surface of the shaft member, and the grease supply hole communicates with the groove. .