JPS6336201Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a planetary roller type power transmission device that transmits power by the frictional force of rollers that are in contact with each other. An example in which a conventional power transmission device of this type is used as a speed reducer is shown in FIGS. 1 and 2. In both figures, 1 is a sun roller directly connected to an input shaft 8 that is rotationally driven, and 3 is a case 10. Inner rollers 2 fixed to the carrier 6 are a plurality of (three in this case) planetary rollers rotatably supported via bearings 4 on planetary pins 5 fixed to the carrier 6.

11 and 12 are bearings.

The sun roller 1, the plurality of planetary rollers 2, and the inner roller 3 apply a pressing force P to these rollers in the radial direction.
Power is transmitted by the frictional force U generated by the pressure contact.

That is, in this case, the inner diameter Di of the inner roller 3 is the sum of twice the outer diameter Ds of the sun roller 1 and the outer diameter Dp of the planetary roller 2 (that is, Ds+
2Dp) and are assembled, and the above-mentioned pressing force P is generated by elastically deforming these rollers and pressing them against each other. In this case, the following problems arose.

(1) In this type of planetary roller type power transmission device, since the pressing force P is always set constant, the frictional force U for transmitting power is also always constant. Therefore, the above-mentioned power transmission device does not have a clutch function for connecting and disconnecting power transmission, and therefore, when an overload is applied, excessive slipping occurs on the respective pressure contact surfaces of the planetary roller 2, the sun roller 1, and the inner roller 3. It is inevitable that a seizing accident will occur and the operation will become impossible.

(2) Also, this kind of planetary roller type power transmission device,
Generally, it is not used alone, but is almost always used as one element of various power transmission circuits. In this case, from the viewpoint of the function, safety, maintenance, inspection, etc. of the entire machine, in practical terms, temporary power interruption and There are many opportunities to connect. In such a case, the above-mentioned power transmission device does not have a power disconnection and connection function, that is, a clutch function, and cannot satisfy such requirements.

The devices shown in FIGS. 3 and 4 have been proposed to solve the above problems.

In the one shown in FIG. 3, a clutch 13 is interposed between the input shafts 8a and 8b, and by engaging and disengaging the clutch 13, the power is transmitted from the input shaft 8a to the planetary roller type power transmission device, and the power transmission is controlled. It's down.

In this case, since the clutch 13 is provided, the axial mounting space Lh of the device becomes larger, and
The additional cost of manufacturing the clutch 13 increases the manufacturing cost of the device.

In the one shown in FIG. 4, a clutch 14 is interposed between the inner roller 3 and the case 10, and by engaging and disengaging the clutch 14, the inner roller 3 can be fixed or released.

In this case, the radial dimension Lv of the device increases and the manufacturing cost also increases.

In FIGS. 3 and 4, the same members as those in FIGS. 1 and 2 are designated by the same reference numerals.

The present invention has been developed in view of the above, and an object of the present invention is to provide a planetary roller type power transmission device that is lightweight, compact, and inexpensive to manufacture by providing the components of the device with a clutch function.

For this reason, the present invention provides a planetary roller type power transmission device in which either one or both of the inner roller or the sun roller is connected to a thin cylindrical portion on which a pressure contact surface with the mating roller is formed, and a thin cylindrical portion that is thicker than the thin cylindrical portion. A thick-walled cylindrical portion having side end surfaces substantially perpendicular to the rotational axis, and a thin-walled disk portion that individually connects both ends of the thin-walled cylindrical portion and one end of the thick-walled cylindrical portion, An elastic roller formed so that the radius of the pressure contact surface with the mating roller can be changed by the pressing force in the axial direction of the rotating shaft applied to the side end surface of the thick-walled cylindrical part, and fluid pressure such as a hydraulic cylinder. The fluid pressure generating device is configured to increase or decrease the pressing force of the elastic roller by an actuating device to attach and detach the pressure contact surface between the elastic roller and a mating roller, and further supplies fluid pressure to the fluid pressure actuating device, A first movable wall defining a portion of an input chamber connected to a fluid generation source via a control valve, and a first movable wall defining a portion of a pressurizing chamber connected to the fluid pressure actuation device and interlocked with the first movable wall. and a second movable wall having a pressurizing area smaller than the pressure receiving area of the first movable wall.

Since the present invention is configured as described above,
It has the following advantages.

(1) Since the power transmission device has a clutch function in the component itself, which was not possible with conventional planetary roller type power transmission devices of this type, it is lighter and smaller than conventional devices equipped with a clutch device. Therefore, the manufacturing cost of the device is also significantly reduced.

(2) Since the clutch can be engaged or disengaged simply by adjusting the pressure of the hydraulic oil acting on the side surface of the elastic roller, the clutch can be engaged or disengaged at any time, whether the power transmission system incorporating the device of the present invention is at rest or in operation. The clutch can be engaged and disengaged, and there is no need to temporarily stop the device to switch the clutch. Moreover, since the fluid pressure generating device is configured to increase the pressure of the fluid pressure generating source and supplying fluid pressure to the fluid pressure actuated device, this device can be used, for example, in automobiles that are not equipped with a very high pressure source. Even when using a fluid pressure operated device, it is possible to reliably obtain the pressure necessary for the fluid pressure operated device, which is extremely useful in practice.

(3) If the device of the present invention is combined with a load torque detection device, and if the load torque of the power transmission system exceeds a limit value, the pressure of the hydraulic oil is reduced and the clutch is disconnected. It can protect the equipment at times.

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 5 to 10. 1 is a sun roller fixed to an input shaft 8, 2 is a plurality of sun rollers supported by a planetary pin 5 via bearings 4. (Three in this example)
The planetary roller 6 is a carrier fixed to the output shaft 20. As shown in FIG. 6, the planetary pin 5 has notches 5a provided at both ends thereof fitted into radial grooves 6a formed in the carrier 6. movably supported.

11a, 11b are bearings of the input shaft 8, 12a, 1
2b is a bearing for the carrier 6 and the output shaft 20.

30 is an annular inner roller having a U-shaped cross section, that is, an elastic roller.

The elastic roller 30 is made of a steel material having wear resistance, and as shown in FIG. , the part forming the side surface 30b to which the pressing force F is applied is constituted by a cylindrical part thicker than the cylindrical part constituting the inner peripheral surface 30a, and both the cylindrical parts are connected by a thin disc part. Because of the shape, a pressing force F is applied to the side surface 30b.
When the width W is reduced to Wo, the radius of the inner circumferential surface 30a is reduced due to the crowning deformation of the thin cylindrical portion. Moreover, since the thick-walled cylindrical portion is not deformed by the pressing force F, the amount of crowning deformation of the thin-walled cylindrical portion,
That is, it is possible to change the radius of the inner peripheral surface 30a substantially proportionally in accordance with the increase or decrease of the pressing force F.

21a is the front case, 21a is the rear case, 1
Numeral 3 is a bolt for fixing the front and rear cases 21a and 21b.

As shown in FIG. 5, the elastic roller 30 has one end fixed to the rear case 21b by a pin 18, and the other side 30b defined by the front case 21a and the outer peripheral surface of the annular inner sleeve 14. It faces the oil chamber 16.

Pressurized hydraulic oil S is introduced into the oil chamber 16 from the oil inlet 19, and the hydraulic oil S is supplied to the elastic roller 3.
By acting on the side surface 30b of 0, a pressing force F in the axial direction is generated.

Reference numeral 17 denotes a spacer inserted between the inner surfaces of the elastic roller 30, and its width B ₂ is formed to be slightly smaller than the width B ₁ of the elastic roller 30. 15
O-rings a, 15b, and 15c are used to seal the hydraulic oil in the oil chamber 16.

As will be described later, when the pressure of the hydraulic oil S is low and the pressing force F acting on the side surface 30b is below a certain value, the elastic roller 30 has an inner circumferential surface 30a and an outer circumferential surface 2a of the planetary roller 2. A gap C is formed between them (FIG. 7a), and when the pressing force F exceeds a certain value, the inner circumferential surface 30a and the outer circumferential surface 2a are pressed together to generate a pressing force P. Can be attached.
Here, various types of hydraulic pressure generating devices can be used to supply hydraulic pressure to the oil chamber 16, but a hydraulic pressure generating device suitable for use when this power transmission device is used in a device having an engine such as a vehicle is suitable. The pressure generating device is shown in FIGS. 8 to 10.

The one shown in Figure 8 uses the negative pressure generated in the engine's intake pipe to generate hydraulic pressure.
Check valve 1 in the intake pipe of the engine (not shown)
Reservoir 10 connected via 01 and storing negative pressure
2 and a diaphragm 103 as a first movable wall, and passages 104 and 1
It has chambers 106 and 107 as input chambers connected to the reservoir 102 by 05, and is fixed to the diaphragm 103 and
an actuating device 110 having a pressurizing chamber 109 that generates hydraulic pressure by a piston 108 as a second movable wall having a pressurizing area smaller than the pressure receiving area of No. 3; and a three-way valve 111 interposed in the passage 105. By rotating the three-way valve 111 90 degrees clockwise from the illustrated state to introduce atmospheric air into the chamber 107, the diaphragm 103 moves to the left in the figure, and the liquid in the pressurizing chamber 109 is pressurized. It is something that will be done. In addition,
112 is a pressure control valve for keeping the pressure in the reservoir 102 constant; 113;
is a return spring of the diaphragm 103. The reservoir 102 can be commonly used for a booster for a brake system in a vehicle or the like.

The one shown in FIG. 9 includes a reservoir 123 that is connected to a compressor 121 driven by an engine (not shown) via a check valve 122 and stores compressed air, and a passageway that is partitioned by a diaphragm 124 as a first movable wall. Chamber 1 as input chamber connected to reservoir 123 by 125
26 and the actuating device 129 having a pressurizing chamber 128 fixed to the diaphragm 124 and generating hydraulic pressure by a piston 127 as a second movable wall having a pressurizing area smaller than the pressure receiving area of the diaphragm 124; Interposed 3-way valve 13
By rotating the three-way valve 90 degrees counterclockwise from the state shown in the figure and introducing compressed air into the chamber 126, the diaphragm 124 moves to the left in the figure and the inside of the pressurizing chamber 128 is moved. The liquid is pressurized. Note that 131 is a pressure control valve for keeping the pressure in the reservoir 123 constant, and 132 is a return spring for the diaphragm 124. The compressor 121, reservoir 123, etc. can be commonly used for a brake system in a vehicle or the like.

The one shown in FIG. 10 is partitioned by an oil pump 143 that is driven by an engine (not shown) and sucks oil in an oil reservoir 141 and discharges it into a passage 142, and a piston 144 as a first movable wall, and is connected to the passage 142. A pressurizing chamber 147 that generates hydraulic pressure by a chamber 145 as an input chamber and a piston 146 as a second movable wall that is fixed to the piston 144 and has a pressurizing area smaller than the pressure receiving area of the piston 144. The device 148 and the oil in the chamber 145 are transferred to the oil reservoir 14.
1, and an on-off valve 150 interposed in the passage 149.
0 is closed, hydraulic pressure is generated in the chamber 145, and the piston 144 moves to the left in the figure to open the pressurized chamber 147.
The liquid inside is pressurized. In addition, 151
is a relief valve for keeping the pressure inside the passage 142 constant. The oil reservoir 141, oil pump 143, etc. can be commonly used for power steering in vehicles, especially automobiles.

In the apparatus shown in FIGS. 5 to 7 described above, hydraulic oil S pressurized to a predetermined pressure is contained in the oil chamber 16.
is introduced, a pressing force F in the axial direction proportional to the pressure of the hydraulic oil S is generated, and when the pressing force F exceeds a certain value, the width W of the elastic roller 30 is reduced and the inner peripheral surface 30a of the elastic roller 30 is reduced. The radius is reduced and the inner peripheral surface 30
a and the outer peripheral surface 2a of the planetary roller 2 are pressed against each other, and a pressing force P is generated.

That is, in FIG. 7, the side surface 3 of the elastic roller 30
When pressing force F is applied to 0a, the axial width W becomes Wo
As a result, the planetary roller 2 of the elastic roller 30
The pressure contact surface 30a forms a crowning deformation E having a radius of curvature r. (FIG. 7b) The free deformation of this crowning deformation E is restricted by e when the sun roller 1 and the planetary roller 2 are assembled. As a result, a pressing force P corresponding to the free deformation amount e is generated.

Since the amount of crowning deformation E increases almost in proportion to the pressing force F, if the assembly interval C between the elastic roller 30 and the planetary roller 2 is taken to be sufficiently small compared to the crowning E, the pressing force F and It becomes almost proportional to the pressure contact force P.

As described above, the planetary roller type power transmission device according to the present invention can perform a clutch action by changing the pressing force F applied to the side surface 30b of the elastic roller 30.

The action of the clutch will be explained below.

(1) When the pressing force F is below a certain value (including the case where no pressing force F is applied; see Fig. 7a), when the pressure of the hydraulic oil S is low and the pressing force F is below a certain value, the elastic roller 30 Since an assembly gap C is formed between the input shaft 8 and the planetary roller 2, even if the input shaft 8 is rotated, the planetary roller 2 simply idles, and the carrier 6 also remains stationary, causing the input shaft 8 to rotate. Transmission of power to the output shaft 20 is cut off. In other words, the clutch becomes disconnected.

(2) When the pressing force F exceeds a certain value (see Fig. 7b), the pressure of the hydraulic oil S increases, and when the pressing force F exceeds a certain value, the elastic roller 30
The width W of is reduced to Wo, and the elastic roller 3
The radius r of the inner circumferential surface 30a of 0 is reduced, the assembly interval 〓C disappears, and a pressing force P is generated between the planetary roller 2, the elastic roller 30, and the sun roller 1.
This pressing force P causes the planetary roller 2, the sun roller 1, and the elastic roller 30 to be pressed against each other.

When the input shaft 8 is rotated in this state, the sun roller 1 rotates, and the planetary rollers 2 revolve while rotating between the sun roller 1 and the elastic roller 30. As a result, the carrier 6 and the output shaft 20 directly connected thereto are rotated in the same direction as the input shaft 8. That is, the sun roller 1 and the planetary roller 2
A frictional force U=Ct·P (Ct is a rolling friction coefficient) is generated on the pressing surfaces 22 and 23 between the planetary roller 2 and the elastic roller 30 due to the pressing force P,
The above-mentioned frictional force U is generated between the input shaft 8 and the output shaft 20.
The power corresponding to is transmitted. In other words, the clutch is in a fitted state.

Note that if the pressure of the hydraulic oil S in the oil chamber 16 becomes excessive, the inner surface of the elastic roller 30 will come into contact with the side surface of the spacer 17 (B ₁ in FIG. 5).
= B ₂ ) This is designed to prevent the pressure contact force P from becoming excessive.

As described above, in the above device, (1) By changing the pressure of the hydraulic oil S in the oil chamber 16, the clutch can be engaged and disengaged both when the device is at rest and when it is in operation.

(2) By gradually increasing the pressure of the hydraulic oil S, the driven body connected to the output shaft can be accelerated.

(3) When the above device and a load torque detection device are combined, the device can be protected by disengaging the clutch in the event of an overload due to the action of the load torque detection device.

There are advantages such as

Furthermore, as described above, the fluid pressure generating device shown in FIGS. 8 to 10 is configured to increase the pressure of the fluid pressure generating source and supply fluid pressure to the oil chamber 16 as a fluid pressure operating device. Therefore, even when this device is used, for example, in an automobile or the like that is not equipped with a very high pressure source, the pressure required for the fluid pressure actuated device can be reliably obtained, and it is extremely useful in practice.

In the above embodiment, the hydraulic oil S in the oil chamber 16
As shown in FIG. 11, the elastic roller 30 is fixed to a cylinder 161 fixed to the case 21a and a piston 162 fitted to the cylinder 161. It is also possible to provide a plurality of actuating devices along the elastic roller 30, each comprising a contact member 163 that abuts on the elastic roller 30.

FIG. 12 shows the main part of another embodiment of the present invention,
In this case, the planetary rollers and inner rollers (elastic rollers) are arranged in a plurality of rows (two rows in this case). That is, in the figure, 41 is a sun roller, 42a, 4
2b is a planetary roller, 43a and 43b are inner rollers that are elastic rollers, 44a and 44b are bearings, and 45
are planetary pins, and 417a and 417b are spacers.

In the case of Fig. 12, Fig. 5 to 1
With the same pressing force F as in the first embodiment shown in FIG.
3a, 43b, the same pressure force P as that in the first embodiment is generated individually, so that it is possible to transmit twice as much power as that in the first embodiment. can.

If the penetrating load of the driven machine connected to this power transmission device is extremely large and the rotational speed at which the driven machine should be accelerated is extremely high, the amount of work of these connections becomes excessive during acceleration, and the pressure contact surfaces 430a, 43
0b seizure accidents often occur, but if the planetary rollers 42a, 42b, inner rollers 43a, 43b, etc. are arranged in multiple rows as in this embodiment, the power transmission capacity increases, which prevents such accidents from occurring. This can be prevented.

In the embodiment shown in FIG. 12, the 13th
As shown in the figure, a cylinder 171 is fixed to one of the elastic rollers 43a and 43b, and a contact member 17 is fixed to a piston 172 fitted in the cylinder 171 and abuts the other of the elastic rollers.
It is also possible to provide a plurality of actuating devices consisting of 3 along each elastic roller.

FIG. 14 shows still another embodiment of the present invention, in which the sun roller is an elastic roller 51, and a pressing force P is generated by applying a pressing force F to the side surface of the elastic roller 51. . That is, in FIG. 9, 51 is a sun roller or elastic roller formed in a U-shaped cross section, 53 is an inner roller fixed to the case 10, 58 is an input shaft, and 54 is a carrier 6.
A plurality of planetary pins (three in this case) are fixed to the planetary roller, 2 is a planetary roller, 4 is a bearing of the planetary roller 2,
20 is an output shaft, and 12b, 511, 512 are bearings. One end 51C of the elastic roller 51 is spline-coupled to the input shaft 8, and the other end 51d is fitted so as to be movable in the axial direction of the input shaft 8. An oil passage 61 is formed in the input shaft 58, and hydraulic oil S is introduced into the oil passage 61 from an oil inlet 10a of the case 10 through a seal metal fitting 62.
63 is a retainer 6 fixed to the end of the input shaft 58
4, and the oil chamber 63 is communicated with the oil passage 61 so that hydraulic oil S is introduced therein. Further, the side surface 51b of the elastic roller 51 faces into the oil chamber 63 and receives the pressure of the hydraulic oil S in the oil chamber 63. 51
7 is an annular spacer for regulating displacement of the input shaft 58 of the elastic roller 51 in the axial direction. 6
5a, 65b are seal rings for sealing hydraulic oil S, 66a, 66b, 67a, 67b are O
-It is a ring.

Note that the elastic roller 51 is moved when the hydraulic oil S is not introduced into the oil chamber 63 or when the pressing force F by the hydraulic oil S is below a certain value.
1 and the outer circumferential surface 2a of the planetary roller 2, and when the pressing force F exceeds a certain value, the mutual outer circumferential surfaces 51a,
2a are assembled in such a manner that they are pressed together and pressure contact force P is generated.

The operation of the device described above is similar to that of the first embodiment shown in FIGS. 5-10. That is, the oil chamber 63
If the hydraulic oil S is not introduced into the
When the pushing force F generated by The clutch is not transmitted, resulting in a state where the clutch is disconnected.

When pressurized hydraulic oil S is introduced into the oil chamber 63 and the pressing force F generated by the hydraulic oil S exceeds a certain value, the pressing force F compresses the elastic roller 51 in the axial direction of the input shaft 58. As the total width is reduced, the radius of the outer circumferential surface 51a increases, and during the above-mentioned assembly
disappears, and both outer circumferential surfaces 51a and 2a are pressed together.
As a result, the elastic roller (sun roller) 51, the planetary roller 2, and the inner roller 53 are pressed against each other by a pressing force P. When the input shaft 8 is rotated in this state, the planetary roller 2 is rotated between the sun roller 51 and the inner roller 53.
The rotation of the input shaft 8 is transmitted to the output shaft 20 via the carrier 6. In other words, the clutch is in a fitted state.

Since the device shown in FIG. 14 has the above-described functions, the same effect as that of the first embodiment shown in FIGS. 5 to 10 can be obtained.

In each of the above embodiments, the elastic roller is brought into pressure contact with the mating roller when a pressing force is applied to the outer surface of the elastic roller.As shown in FIG. An actuating device formed in advance so as to come into pressure contact with the mating roller 2, and comprising a cylinder 181 and an abutting member 183 fixed to a piston 182 fitted in the cylinder 181 is provided in the elastic roller 30, Hydraulic pressure acts within the cylinder 181, causing the elastic roller 3 to
It is also possible to configure such that when the roller 0 is expanded in the axial direction, the pressure contact of the elastic roller 30 with respect to the mating roller 2 is released and the power transmission is cut off.

Furthermore, in each of the above embodiments, to deform the elastic roller, a hydraulic actuator operated directly or by hydraulic pressure is used, but an actuator actuated by gas pressure is used. It is also possible to use

[Brief explanation of drawings]

1 and 2 show an example of a conventional planetary roller type power transmission device, in which FIG. 1 is a cross-sectional view along the axis of the input shaft, FIG. 2 is a cross-sectional view along the - line in FIG. 1, 3 and 4 are power system diagrams each using a conventional planetary roller type power transmission device.
5 to 7 show one embodiment of the present invention,
Figure 5 is a partial cross-sectional view along the axis of the input shaft;
The figure is a view taken along the - line in Fig. 5, Fig. 7 is an elastic surface view of an elastic roller, Fig. 8 is an explanatory diagram showing an example of a hydraulic pressure generating device, and Fig. 9 shows another example. The explanatory diagram, FIG. 10, is an explanatory diagram showing still another example.
FIG. 11 is a sectional view of a main part showing a modification of the first embodiment. FIG. 12 is a cross-sectional view of a main part showing another embodiment of the present invention, FIG. 13 is a cross-sectional view of a main part showing a modification of the above-mentioned other embodiment, and FIG. 14 is a cross-sectional view of a main part showing another embodiment of the present invention. FIG. 15, which corresponds to FIG. 5, is a sectional view of a main part showing another modification. 1, 41... Sun roller, 51... Sun roller (elastic roller), 2, 42a, 42b... Planetary roller, 30, 43a, 43b... Inner roller (elastic roller), 53... Inner roller, 8, 58...Input shaft,
6...Carrier, 20...Output shaft, 16, 63...
...Oil chamber, 22, 23, 430a, 430b...pressure contact surface.

Claims (1)

[Scope of utility model registration request] The outer periphery of a sun roller that is connected to one of the rotating shafts so that it cannot move in the circumferential direction thereof, and the inner periphery of an inner roller that is attached to a stationary member so that it cannot move in the circumferential direction of the rotating shaft, respectively. In an apparatus that transmits power between the two rotating shafts by supporting a plurality of planetary rollers by a carrier connected to the other rotating shaft, either one of the inner roller or the sun roller or A thin cylindrical portion formed with a pressure contact surface with the mating roller, a thick cylindrical portion formed thicker than the thin cylindrical portion and having a side end surface substantially perpendicular to the rotation axis, and the thin cylindrical portion a thin-walled cylindrical section that individually connects both ends of the cylindrical section and one end of the thick-walled cylindrical section; An elastic roller is used in which the radius of the pressure contact surface with the mating roller can be changed, and by applying a pressing force to the side end surface of the elastic roller and increasing or decreasing the pressing force, the pressure contact surfaces of the elastic roller and the mating roller are attached and detached. a fluid pressure actuated device that is connected to the fluid pressure actuated device and supplies fluid pressure to the fluid pressure actuated device; a first movable wall that defines a part of the input chamber connected to the fluid pressure actuator; A planetary roller type power transmission device comprising: a second movable wall having a pressure area smaller than a pressure receiving area.