CN205278282U

CN205278282U - Harmonic gear drive

Info

Publication number: CN205278282U
Application number: CN201520908937.9U
Authority: CN
Inventors: 冈村晖久夫; 井上仁
Original assignee: Nidec Shimpo Corp
Current assignee: Nidec Drive Technology Corp
Priority date: 2014-11-19
Filing date: 2015-11-13
Publication date: 2016-06-01
Anticipated expiration: 2025-11-13
Also published as: JP2016098866A; CN105605190A; CN105605190B; JP6490404B2

Abstract

Harmonic gear drive has: annular rigidity internal gear, dispose in the annular flexible external gear and the wave generator of the radial inboard of rigidity internal gear, this wave generator disposes in the radial inboard of flexible external gear to compare with flexible external gear, can be relatively high -speed rotatory. Make flexible external gear mesh partly at the footpath kickup and with the rigidity internal gear through wave generator to make the position of engagement in all rebounds, thereby make and have relatively low -spin of the poor rigidity internal gear of the number of teeth and flexible external gear. Flexible external gear has along axially extended drum portion and follow one end along the radial dish portion of extending of drum portion. This harmonic gear drive has: low -spin axle, torque transmission parts and torque restraining device, this torque transmission parts is being fixed in the low -spin axle with set portion position of opposition in the axial, the transmission of dish portion to torque transmission parts's torque is followed in the restriction of torque restraining device.

Description

Harmonic gear drive

Technical field

The utility model relates to a kind of harmonic gear drive. More specifically, relate to the improvement of a kind of harmonic gear drive, this harmonic gear drive makes flexible outer rotor bending diametrically by wave producer and locally engages with rigid internal gear, and engagement position is moved in the circumferential, thus make rigid internal gear and flexible outer rotor relative to rotate.

Background technology

Harmonic gear-type step-down gear be a kind of can easily obtain about 1/50 high reduction ratio, and carry on the back the small-sized deceleration device that gap is little. Harmonic gear-type step-down gear can be used in driving the actuator etc. of mechanical arm. Such as in Japanese Unexamined Patent Publication Heisei 11-118003 publication, disclose this kind of step-down gear. The harmonic gear drive 1 that Japanese Unexamined Patent Publication Heisei 11-118003 publication is recorded is a kind of harmonic gear-type step-down gear, the wave producer 4 of the rigid internal gear 2 that this step-down gear has ring-type, the flexible outer rotor 3 of ring-type being configured at the inner side of rigid internal gear 2 and the inner side of the flexible outer rotor 3 of embedding. The revolving force of electronic motor is slowed down and exports by harmonic gear drive 1.

Wave producer 4 has the outline shape of elliptical shape etc., and is bent in radius direction and form the state locally engaged with rigid internal gear 2 by flexible outer rotor 3. Wave producer 4 is by being connected with the high-speed rotating shaft of electronic motor, and the engagement position making two gears is moved in a circumferential direction, thus produces the relative rotary motion of the number of teeth difference corresponding to two gears between two gears. Rigid internal gear 2 is fixed on the machine shell etc. of electronic motor, and obtains the output that is rotated in deceleration from flexible outer rotor 3.

Harmonic gear drive 1 has torque-limiting mechanism, the torque that this torque-limiting mechanism transmits for being limited between high-speed rotating shaft and wave producer 4. This torque-limiting mechanism is formed by by nut 46 fastening with wheel hub 43 for the rigid convex wheel plate 41 of wave producer 4. As described in Japanese Unexamined Patent Publication Heisei 11-118003 publication, when the transmission of torque state that generation regulation is above, producing the slip of sense of rotation between rigid convex wheel plate 41 and wheel hub 43, torque-limiting mechanism will transmit torque limitation in the limit of regulation.

In above-mentioned existing harmonic gear drive, in order to protect electronic motor from exceeding in the excessive loads of withstand load, the torque restricting means that torque is transmitted in restriction is configured at high-speed rotating shaft side. By arranging such torque restricting means, when transmitting torque and exceed higher limit, owing to being cut off from wave producer to the transmission of the torque of high-speed rotating shaft, therefore, it is possible to protect electronic motor. But, harmonic gear drive is when inputting revolving force by low-speed rotary shaft, and flexible outer rotor non rotating, becomes so-called self-locking state. Therefore, in above-mentioned existing harmonic gear drive, harmonic gear drive itself can not be protected from the excessive revolving force inputted by low-speed rotary shaft.

Such as, when the articular portion of robot is configured with the actuator with harmonic gear drive, if the movable portion of robot collides with people etc. at work, the revolving force produced by collision is through power transfer path back transfer, and this power transfer path is the path that power is passed to via harmonic gear drive driven object object from electronic motor. At this moment, the harmonic gear drive forming power transfer path becomes self-locking state. Therefore, there is the flexible outer rotor that by low-speed rotary shaft, the excessive revolving force caused because colliding is acted on harmonic gear drive, and make the worry of flexible outer rotor viscous deformation or damage.

Practical novel content

In view of above problem, the purpose of this utility model is to provide a kind of raising to the harmonic gear drive of the tolerance being inputted excessive revolving force by low-speed rotary shaft.

In the enforcement mode illustrated in the application, harmonic gear drive has: the rigid internal gear of ring-type; Flexible outer rotor, described flexible outer rotor is ring-type, and is configured at the radially inner side of described rigid internal gear; And wave producer, described wave producer is configured at the radially inner side of flexible outer rotor, and compared with flexible outer rotor, it is possible to high speed rotating relatively. Make flexible outer rotor bending diametrically by fluctuation generator and with the engaging of rigid internal gear local, and engagement position is moved in the circumferential, thus make the rigid internal gear that there is number of teeth difference relative with flexibility outer rotor low speed rotation. Flexible outer rotor has: cylindrical portion, and described cylindrical portion extends vertically; And dish portion, described dish portion radially extends from one end of cylindrical portion. Harmonic gear drive has: low-speed rotary shaft; Torque transmission member, the position put is being fixed in low-speed rotary shaft with dish portion by torque transmission member in the axial direction; And torque restricting means, described torque restricting means limits from dish portion to the transmission of the torque of torque transmission member.

Torque restricting means has: one to friction plate, described one to friction plate from axial holding tray portion, both sides; And force application part, dish portion is exerted a force by described force application part in the axial direction towards torque transmission member.

Force application part is configured at the position of the other end side leaning on cylindrical portion in the axial direction than dish portion.

Dish portion has the toroidal extended from one end of cylindrical portion to radially inner side, and the force application part of torque restricting means is configured at the radially inner side of cylindrical portion.

Dish portion has the toroidal extended from one end of cylindrical portion to radial outside, and the force application part of torque restricting means is configured at the radial outside of cylindrical portion.

Harmonic gear drive has: crossed roller bearing, and described crossed roller Bearing configuration is in the radial outside of rigid internal gear, and supports low-speed rotary shaft for rotating relative to rigid internal gear. Torque transmission member has the toroidal extended from the inner peripheral surface of low-speed rotary shaft to radially inner side. Force application part is configured in the position than side, crossed roller Bearing support dish portion in the axial direction.

Torque restricting means has: pressing plate, and the dish portion of the flexible outer rotor of described pressing plate restriction moves in the axial direction relative to torque transmission member; Can untie-sell, described can untie-sell be configured to can move in the axial direction relative to dish portion, and through described dish portion; And force application part, described force application part can untie-sell axial relative to low speed rotation torque transmission member side force. Torque transmission member has recess, and described recess can the terminal part of untie-sell be contained in dish portion the dish opposed faces put. Recess restriction can be moved relative to torque transmission member in the circumferential in untie-sell.

Dish portion has the toroidal extended from one end of cylindrical portion to radially inner side, and the pressing plate of torque restricting means and force application part are configured at the radially inner side of cylindrical portion.

Torque restricting means has: pressing plate, and the dish portion of the flexible outer rotor of described pressing plate restriction moves in the axial direction relative to torque transmission member; Transmission of torque ball, described transmission of torque ball is contained in the communicating pores in through dish portion, and can move in the axial direction relative to dish portion; And force application part, torque transmission member side axial relative to low speed rotation for transmission of torque ball is exerted a force by described force application part. Torque transmission member has recess, and a part for transmission of torque ball is contained in dish portion the dish opposed faces put by recess. Recess torque-limiting transmission ball moves in the circumferential relative to torque transmission member.

Force application part is made up of dish spring or whisker.

Torque restricting means has pressing plate, and the dish portion of the flexible outer rotor of described pressing plate restriction moves in the axial direction relative to torque transmission member. Dish portion has protuberance, and described protuberance is outstanding to torque transmission member side in the axial direction. Torque transmission member has recess, and protuberance is contained in dish portion the dish opposed faces put by described recess. Recess restriction protuberance moves in the circumferential relative to torque transmission member.

In the enforcement mode illustrated in the application, harmonic gear drive has: the rigid internal gear of ring-type; Flexible outer rotor, described flexible outer rotor is ring-type, and is configured at the radially inner side of rigid internal gear; And wave producer, described wave producer is configured at the radially inner side of flexible outer rotor, and compared with flexible outer rotor, it is possible to high speed rotating relatively. The number of teeth of rigid internal gear is different from the number of teeth of flexible outer rotor. While flexible outer rotor locally engages with rigid internal gear and bend diametrically relative to rigid internal gear, rigid internal gear can low speed rotation relative to wave producer with flexibility outer rotor. Flexible outer rotor has: cylindrical portion, and described cylindrical portion extends vertically; And dish portion, described dish portion radially extends from one end of cylindrical portion. Harmonic gear drive has: low-speed rotary shaft; Torque transmission member, the position put is being fixed in low-speed rotary shaft with dish portion by described torque transmission member in the axial direction; And torque restricting means, described torque restricting means contacts with torque transmission member.

Torque restricting means has: pressing plate, and the described dish portion of the flexible outer rotor of described pressing plate restriction moves in the axial direction relative to described torque transmission member; Can untie-sell, described can untie-sell be configured to can move in the axial direction relative to dish portion, and through dish portion; Force application part, described force application part can untie-sell axial relative to low speed rotation torque transmission member side force; And recess, the restriction of described recess can be moved relative to torque transmission member in the circumferential in untie-sell. Torque transmission member can the terminal part of untie-sell be contained in dish portion the dish opposed faces put.

Torque restricting means has: pressing plate, and the dish portion of the flexible outer rotor of described pressing plate restriction moves in the axial direction relative to torque transmission member; Transmission of torque ball, described transmission of torque ball is contained in the communicating pores in through dish portion, and can move in the axial direction relative to dish portion; Force application part, torque transmission member side axial relative to low speed rotation for transmission of torque ball is exerted a force by described force application part; And recess, described recess torque-limiting transmission ball moves in the circumferential relative to torque transmission member. A part for transmission of torque ball is contained in dish portion the dish opposed faces put by torque transmission member.

Torque restricting means is limited between the dish portion of the torque transmission member being fixed on low-speed rotary shaft and flexible outer rotor the torque transmitted. Therefore, harmonic gear drive is when inputting excessive revolving force by low-speed rotary shaft, it is possible to produce the slip of circumference between low-speed rotary shaft and flexible outer rotor.

In an enforcement mode of the application, harmonic gear drive when inputting excessive revolving force by low-speed rotary shaft, owing to producing to slide between low-speed rotary shaft and flexible outer rotor, accordingly, it may be possible to prevent flexible outer rotor viscous deformation or damage.

With reference to accompanying drawing and by the following detailed explanation to preferred implementation, above-mentioned and other key elements, feature, step, feature and advantage of the present utility model can become clearly.

Accompanying drawing explanation

Fig. 1 is the sectional view of the harmonic gear drive 100 involved by enforcement mode 1.

Fig. 2 is the sectional view of the harmonic gear drive 100 involved by enforcement mode 2.

Fig. 3 is the figure of the dish opposed faces 32 illustrating torque transmission member 3.

Fig. 4 is the sectional view of the harmonic gear drive 100 involved by enforcement mode 3.

Fig. 5 is the sectional view of the harmonic gear drive 100 involved by enforcement mode 4.

Fig. 6 is the sectional view of the harmonic gear drive 100 involved by enforcement mode 5.

Fig. 7 is the figure observing flexible outer rotor 12 from input side.

Fig. 8 is the sectional view of the harmonic gear drive 100 involved by enforcement mode 6.

Fig. 9 is the sectional view of the harmonic gear drive 100 involved by enforcement mode 7.

Embodiment

Hereinafter, with reference to accompanying drawing, the enforcement mode illustrated in the application is described. Although in this manual, for convenience of explanation and using the direction of rotation center axis as horizontal direction, but it is not defined as the attitude in use of the harmonic gear drive involved by the utility model. In this manual, by the direction of rotation center axis referred to as " axis ", by the radial direction centered by rotation center axis with circumference referred to as " radial direction " and " circumference ".

Enforcement mode 1

Fig. 1 is the sectional view of the configuration example illustrating the harmonic gear drive 100 involved by an enforcement mode that the application illustrates. Figure 1 illustrates cross section when harmonic gear drive 100 cutting being opened by the plane comprising rotation center axis J.

Harmonic gear drive 100 is the deceleration device rotary motion obtained from electronic motor (not shown) being slowed down and exporting. Harmonic gear drive 100 has harmonic gear-type step-down gear 1, low-speed rotary shaft 2, torque transmission member 3 and torque restricting means 4. In FIG, using the right side in figure face as input side, using left side as outgoing side, draw the harmonic gear drive 100 that torque restricting means 4 is configured at outgoing side.

Step-down gear 1

The flexible outer rotor 12 of rigid internal gear 11 that step-down gear 1 has ring-type, the ring-type being configured at the radially inner side of rigid internal gear 11 and be configured at the wave producer 13 of the radially inner side of flexible outer rotor 12. Wave producer 13 is compared with flexible outer rotor 12, it is possible to high speed rotating relatively.

Rigid internal gear 11

Rigid internal gear 11 is the gear in inner circumferential with multiple tooth (that is, internal tooth (omitting diagram)). Rigid internal gear 11 is preferably formed by metal rigid body. Such as, the machine shell that rigid internal gear 11 is fixed on electronic motor shares. Rigid internal gear 11 has open holes 111,112. Harmonic gear drive 100 is such as fixed on machine shell etc. by screw etc. via open holes 111,112.

Flexible outer rotor 12

Flexible outer rotor 12 is the gear in periphery with multiple tooth (that is, external tooth (omitting diagram)). Flexible outer rotor 12 is preferably formed by metallic elastic body. Flexible outer rotor 12 has cylindrical portion 121 and dish portion 122. Cylindrical portion 121 extends vertically. Dish portion 122 radially extends from one end of cylindrical portion 121. In this preferred implementation, flexible outer rotor 12 is for there being end drum. Dish portion 122 extends from the end of the outgoing side of cylindrical portion 121 to radially inner side. The number of teeth of the gear ratio rigid internal gear 11 of flexible outer rotor 12 is few.

The external tooth of flexible outer rotor 12 is configured at the end of the input side of cylindrical portion 121. Dish portion 122 is the bottom of toroidal. Inner peripheral edge portion in dish portion 122 is configured with thick wall portion 6. The thickness of the axis of thick wall portion 6 is thicker than the axial thickness in other region. The inner peripheral surface of thick wall portion 6 and the periphery of low-speed rotary shaft 2 are arranged opposite. That is, dish portion 122 has the toroidal extended from one end of cylindrical portion 121 to radially inner side.

Wave producer 13

In wave producer 13, bent diametrically by flexible outer rotor 12, and flexible outer rotor 12 locally is engaged relative to rigid internal gear 11. Wave producer 13 by the revolving force of electronic motor compared with flexible outer rotor 12 high speed rotating comparatively relatively, the position that flexible outer rotor 12 is engaged with rigid internal gear 11 is moved in the circumferential. By the effect of such wave producer 13, make rigid internal gear 11 low speed rotation relatively with flexible outer rotor 12 that there is number of teeth difference. That is, the number of teeth of rigid internal gear 11 is different from the number of teeth of flexible outer rotor 12. While flexible outer rotor 12 locally engages with rigid internal gear 11 and bend diametrically relative to rigid internal gear 11. By this structure, rigid internal gear 11 and flexible outer rotor 12 can relative to wave producer 3 low speed rotation relatively.

Wave producer 13 has flexible bearing 131 and rigid convex wheel plate 132. Flexible bearing 131 is configured at the radially inner side of flexible outer rotor 12. Rigid convex wheel plate 132 is configured at the radially inner side of flexible bearing 131.

By rigid convex wheel plate 132 rotary motion centered by rotation center axis J, make the shake of the generation radial direction in flexible bearing 131 and flexible outer rotor 12 cycle. Rigid convex wheel plate 132 is preferably formed by metal rigid body. The shape of the periphery of rigid convex wheel plate 132 is preferably elliptical shape. Embedded the inner peripheral surface of the flexible bearing 131 of the inner side being configured in flexible outer rotor 12 by rigid convex wheel plate 132, and make flexible outer rotor 12 and flexible bearing 131 be deformed into elliptical shape. When this kind of flexible outer rotor 12 and flexible bearing 131 are deformed into elliptical shape, the position that flexible outer rotor 12 engages with rigid internal gear 11 is positioned at the two ends of oval major axis.

Rigid convex wheel plate 132 has axis hole 1321. Axis hole 1321 is by communicating pores through in the axial direction for rigid convex wheel plate 132. The axle (not shown) of electronic motor is contained in axis hole 1321. Axis hole 1321 has at least one keyway 1322. Time in axle insertion axis hole 1321, it is possible to by keyway 1322, rigid convex wheel plate 132 is fixed on axle.

Flexible bearing 131 is for support flexibility outer rotor 12 as rotating relative to rigid convex wheel plate 132. This preferred embodiment in, flexible bearing 131 is ball bearing. Flexible bearing 131 has outer ring, is configured at the inner ring of the radially inner side of outer ring and multiple spherical rolling body. Outer ring and inner ring are preferably formed by metallic elastic body. Multiple spherical rolling body is configured between outer ring and inner ring. But, flexible bearing 131 can also be the bearing beyond ball bearing.

When turning clockwise from input side observation wave producer 13, the position that rigid internal gear 11 engages with flexible outer rotor 12 is also moved clockwise. At this moment, owing to the number of teeth of the gear ratio rigid internal gear 11 of flexible outer rotor 12 is few, therefore flexible outer rotor 12 is rotated counterclockwise.

Embedded the inner side of flexible bearing 131 by rigid convex wheel plate 132 from input side, flexible bearing 131 is configured on the side face of rigid convex wheel plate 132 (that is, periphery side). When flexible bearing 131 is installed on rigid convex wheel plate 132, wave producer 13 embeds the inner side of flexible outer rotor 12.

Low-speed rotary shaft 2

Low-speed rotary shaft 2 is the axle of the output of low speed rotation centered by rotation center axis J. Low-speed rotary shaft 2 and rigid internal gear 11 arranged coaxial, and the revolving force of step-down gear 1 is exported. Being positioned in low-speed rotary shaft 2 is thicker than the external diameter at the position of the outgoing side being positioned at low-speed rotary shaft 2 by the external diameter at the position of outgoing side than torque transmission member 3. Preferably form screw thread in the end of the input side of low-speed rotary shaft 2. Adjustment screw 45 described later is fastened to screw thread place.

Torque transmission member 3

The revolving force of flexible outer rotor 12 is passed to low-speed rotary shaft 2 by torque transmission member 3. At flexible outer rotor 12 with dish portion 122 in the axial direction to the position put, torque transmission member 3 is fixed on low-speed rotary shaft 2. Such as, torque transmission member 3 is the plate member of ring-type of the side face surrounding low-speed rotary shaft 2, and preferably and low-speed rotary shaft 2 form as one.

Torque restricting means 4

Torque restricting means 4 contacts with torque transmission member 3. Torque restricting means 4 is limit from the dish portion 122 of flexible outer rotor 12 to the transmission of the torque of torque transmission member 3. According to this structure, torque restricting means 4 can transmit the torque being no more than higher limit, and can cut off the torque exceeding higher limit.

In this embodiment, torque restricting means 4 is friction clutch. Torque restricting means 4 have one pair of friction plate 41,42, pressing plate 43, dish spring 44 and adjustment screw 45. Friction plate 41,42 is from axial holding tray portion, both sides 122.

Pressing plate 43, dish spring 44 and adjustment screw 45 are configured at the position of the other end side leaning on cylindrical portion 121 than dish portion 122 in the axial direction. In more detail, pressing plate 43, dish spring 44 and adjustment screw 45 are configured at the other end side of the cylindrical portion 121 of input side. That is, pressing plate 43, dish spring 44 and adjustment screw 45 are configured at the position leaning on side, dish portion 122 than the end of input side. Pressing plate 43, dish spring 44 and adjustment screw 45 are configured at the radially inner side of cylindrical portion 121.

Wave producer 13 in the axial direction external tooth forming region 5 with flexible outer rotor 12 configure with repeating. Pressing plate 43, dish spring 44 and adjustment screw 45 are configured at the position leaning on outgoing side than external tooth forming region 5.

Friction plate 41,42

Friction plate 41,42 controls to transmit the higher limit of torque. The shape of friction plate 41,42 is surround the toroidal of low-speed rotary shaft 2. Friction plate 41 is configured between torque transmission member 3 and dish portion 122. The side of the input side of friction plate 41 contacts with thick wall portion 6. The side of the outgoing side of friction plate 41 contacts with torque transmission member 3. Friction plate 42 is configured between dish portion 122 and pressing plate 43. The side of the outgoing side of friction plate 42 contacts with thick wall portion 6. The side of the input side of friction plate 42 contacts with pressing plate 43.

Pressing plate 43

Pressing plate 43 is confinement plate portion 122 relative to torque transmission member 3 movement in the axial direction. Pressing plate 43 has the toroidal surrounding low-speed rotary shaft 2. Pressing plate 43 can move in the axial direction. Pressing plate 43 limits the rotation to circumference relative to low-speed rotary shaft 2 by spline pin 431.

Spline pin 431 is the bar-shaped parts radially extended. The periphery of low-speed rotary shaft 2 has the hole of pin insertion. Spline pin 431 is fixed on low-speed rotary shaft 2 by the hole of insertion pin insertion. The terminal part of spline pin 431 is given prominence to from the periphery of low-speed rotary shaft 2. The inner peripheral surface of pressing plate 43 has the cotter way 432 extended vertically. By the terminal part of spline pin 431 is contained in cotter way 432, pressing plate 43 can relative to low-speed rotary shaft 2 to while moving axially, restriction relative to low-speed rotary shaft 2 to the rotation of circumference.

Dish spring 44

Torque restricting means 4 has the force application part exerted a force in dish portion 122 in the axial direction towards torque transmission member 3. Force application part is preferably made up of dish spring 44 or whisker 51. In the present embodiment, force application part is dish spring 44. Can in the axial direction by torque restricting means 4 slimming according to this structure. Owing to can pass through simple Structure composing torque restricting means 4, therefore the manufacture of harmonic gear drive 100 becomes easy. By force application part being changed to the different parts of elasticity, or friction plate 41 is changed to the different parts etc. of frictional coefficient, it is possible to easily adjust the higher limit of torque. Dish spring 44 is the force application part exerted a force to torque transmission member 3 side of axis relative to low-speed rotary shaft 2 in dish portion 122. Dish spring 44 has the shape surrounding low-speed rotary shaft 2, and the stress according to axis produces elasticity distortion. Dish spring 44 is configured between pressing plate 43 and adjustment screw 45, and by pressing plate 43 to axial outgoing side force. Force application part is configured at the position of the other end side leaning on cylindrical portion 121 than dish portion 122 in the axial direction. According to this structure, in the axial direction owing to force application part can be configured at and the position that cylindrical portion 121 repeats, therefore, it is possible to shorten the length of the axis of harmonic gear drive 100.

Adjustment screw 45

Adjustment screw 45 is the force adjustment component that adjustment dish spring 44 exerts a force. Adjustment screw 45 has twists, with low-speed rotary shaft 2, the nut connect. Moved in the axial direction by adjustment screw 45, the force of adjustment dish spring 44. By adjusting the force of dish spring 44, pressure is pressed by friction plate 41,42 by adjustment one by dish portion 122. Accordingly, it may be possible to the higher limit of torque is transmitted in control.

The each part forming the harmonic gear drive 100 involved by present embodiment is described above. Hereinafter, the mutual relationship of these parts and the action effect that produced by them are described in detail.

(1) to the tolerance of excessive revolving force

In the harmonic gear drive 100 involved by present embodiment, when the higher limit transmitting torque is set as the torque damaged below the value of flexible outer rotor 12, when excessive revolving force being inputed to harmonic gear drive 100 by low-speed rotary shaft 2, by the effect of torque restricting means 4, produce to slide between torque transmission member 3 and dish portion 122. Accordingly, it may be possible to prevent flexible outer rotor 12 from producing viscous deformation or damage for the excessive revolving force inputted by low-speed rotary shaft 2. According to above-mentioned structure, compared with the situation becoming thick with the wall thickness making flexible outer rotor 12 and gain in strength, it is possible to suppress to transmit the increase of loss.

(2) slimming of harmonic gear drive 100

In the harmonic gear drive 100 involved by present embodiment, pressing plate 43, dish spring 44 and adjustment screw 45 configure with cylindrical portion 121 in the axial direction with repeating. That is, pressing plate 43 and force application part are configured at the inner side of cylindrical portion 121. Therefore, with pressing plate 43, dish spring 44 and adjustment screw 45 be configured at than dish portion 122 by outgoing side position compared with, and compared with the situation being configured to lean out from cylindrical portion 121, it is possible to by harmonic gear drive 100 slimming in the axial direction.

In harmonic gear drive 100, pressing plate 43, dish spring 44 and adjustment screw 45 are configured in the cylindrical portion 121 of flexible outer rotor 12. Therefore, compared with the radial outside that pressing plate 43, dish spring 44 and adjustment screw 45 are configured at cylindrical portion 121, it is possible to by harmonic gear drive 100 miniaturization diametrically.

(3) minimizing of loss is transmitted

In harmonic gear drive 100, if the rigidity decline of cylindrical portion 121, then flexible outer rotor 12 becomes easily bending, thus flexible outer rotor 12 becomes easy with rigid internal gear 11 engages. Its result is, loss when transmitting torque from flexible outer rotor 12 to torque transmission member 3 diminishes. Therefore, the thickness of flexible outer rotor 12 is preferably thin. But, if the thickness of flexible outer rotor 12 is thinning, then there is the excessive revolving force owing to being inputted by low-speed rotary shaft 2 and damage the worry of flexible outer rotor 12. To this, in the harmonic gear drive 100 involved by present embodiment, between flexible outer rotor 12 and low-speed rotary shaft 2, it is provided with torque restricting means 4. Therefore, even if when flexible outer rotor 12 being applied bigger power, it is also possible to suppress the damage of flexible outer rotor 12. Therefore, the thickness of flexible outer rotor 12 can be thinning further. Its result is, owing to the rigidity of flexible outer rotor 12 reduces, it is possible to reduce and transmit loss.

(4) easyization of torque adjustment

In the harmonic gear drive 100 involved by present embodiment, torque restricting means 4 have one pair of friction plate 41,42, pressing plate 43, dish spring 44 and adjustment screw 45. Therefore, harmonic gear drive 100 can easily adjust the higher limit of the torque can transmitted between torque transmission member 3 and the dish portion 122 of flexible outer rotor 12.

Particularly, harmonic gear drive 100 moves, owing to adjusting screw 45 by rotation, the force adjusting dish spring 44 in the axial direction, therefore, it is possible to easily adjust the higher limit transmitting torque. By dish spring 44 is changed to the different parts of coefficient of elasticity, or friction plate 41,42 is changed to the different parts of frictional coefficient, or pressing plate 43 is changed to the different parts of thickness, it is possible to the higher limit of torque is transmitted in fine setting further.

(5) simplification of torque restricting means

In the harmonic gear drive 100 involved by present embodiment, torque restricting means 4 has friction clutch. Therefore, torque restricting means 4 is compared with during the clutch coupling with engagement formula, and torque restricting means 4 turns into simple structure, and the manufacture of harmonic gear drive 100 becomes easy. In addition, torque restricting means 4 can also have the clutch coupling of engagement formula.

(6) deviation of upper limit torque is suppressed

In the harmonic gear drive 100 involved by present embodiment, limit the rotation of pressing plate 43 relative to low-speed rotary shaft 2 by spline pin 431. Accordingly, it may be possible to suppress the deviation of the higher limit of the torque can transmitted between torque transmission member 3 and dish portion 122.

The structure of torque transmission member 3 is not defined as above-mentioned structure. Such as, torque transmission member 3 can also be and the parts of low-speed rotary shaft 2 split, and be fixed on low-speed rotary shaft 2.

The structure of torque restricting means 4 is not defined as above-mentioned structure. Such as, it is also possible in the axial direction, torque transmission member 3 is configured at the position leaning on input side than the dish portion 122 of flexible outer rotor 12, and pressing plate 43, dish spring 44 and adjustment screw 45 are configured at the position leaning on outgoing side than dish portion 122.

Force application part is not defined as above-mentioned parts. Such as, force application part can also be the whisker of through low-speed rotary shaft 2.

The structure of the rotation of restriction pressing plate 43 is not defined as said structure. The terminal part of the spline parts of key (Key) or spline (Spline) etc. is fixed on pressing plate 43 with the state outstanding from the inner peripheral surface of pressing plate 43. The periphery of low-speed rotary shaft 2 has the groove that can hold spline parts extended vertically. By being contained in this groove by the terminal part of spline parts, pressing plate 43 to moving axially, and can limit pressing plate 43 to rotating in a circumferential direction.

In the first embodiment, the situation that torque restricting means 4 is made up of friction clutch is illustrated. In the preferred implementation of the 2nd following to the 5th, the situation that torque restricting means 4 is made up of engaged clutch is described.

2nd preferred implementation

Fig. 2 is the sectional view of the configuration example illustrating the harmonic gear drive 100 involved by the 2nd preferred implementation, illustrates the cross section of torque restricting means 4. Cross section when harmonic gear drive 100 cutting being opened by the plane comprising rotation center axis J is shown in the drawings. In fig. 2, the position in side more top than rotation center axis J is shown, the terminal part of untie-sell 46 can be contained in the state of recess 31 of torque transmission member 3. In the same figure, illustrate than rotation center axis J position on the lower, untie-sell 46 can move to the state of position of deviation recess 31. Fig. 3 is the figure of the dish opposed faces 32 illustrating torque transmission member 3 illustrated in fig. 2.

The structure of the harmonic gear drive 100 involved by the 2nd preferred implementation is compared with the structure of the harmonic gear drive 100 shown in Fig. 1, and torque transmission member 3 is different with the structure of torque restricting means 4. In the end of the input side of low-speed rotary shaft 2, form the screw thread twisted and connect adjustment screw 45.

Torque transmission member 3

Torque transmission member 3 has at least one recess 31. In this preferred implementation, the number of recess 31 is eight. Recess 31 is configured at the dish portion 122 with flexible outer rotor 12 to the dish opposed faces 32 put. Recess 31 hold described later can the terminal part of untie-sell 46. Dish opposed faces 32 is the side of the input side of torque transmission member 3.

From, when axially observing, the shape of the opening of recess 31 is such as circular. The cross-sectional shape opened by the plane cutting parallel with rotation center axis J of recess 31 is such as the circular cone cave of trilateral. In dish opposed faces 32, it is circumferentially same that the recess 31 of two or more is configured at centered by rotation center axis J. Each recess 31 configures across constant interval in the circumferential. In torque transmission member 3 as shown in Figure 3, ground, the interval configurations such as eight recesses 31.

Torque restricting means 4

Torque restricting means 4 is the clutch coupling of engagement formula, have adjustment screw 45, can untie-sell 46, auxiliary plate 47, pressing plate 48 and dish spring 49. Adjustment screw 45, auxiliary plate 47, pressing plate 48 and dish spring 49 are configured at the position of the other end side leaning on cylindrical portion 121 than the dish portion 122 of flexible outer rotor 12 in the axial direction. That is, the other end side that screw 45, auxiliary plate 47, pressing plate 48 and dish spring 49 are configured at the cylindrical portion 121 of input side is adjusted. In more detail, adjustment screw 45, auxiliary plate 47, pressing plate 48 and dish spring 49 are configured at and lean on side, dish portion 122 than the end of input side. Adjustment screw 45, auxiliary plate 47, pressing plate 48 and dish spring 49 are configured at the radially inner side of cylindrical portion 121. That is, the force application part of torque restricting means 4 is configured at the radially inner side of cylindrical portion 121. Thus, owing to force application part does not lean out laterally from the cylindrical portion 121 of flexible outer rotor 12, therefore harmonic gear drive 100 can miniaturization further.

Auxiliary plate 47 is the spacer of the toroidal surrounding low-speed rotary shaft 2. Auxiliary plate 47 is configured between dish portion 122 and pressing plate 48. Auxiliary plate 47 has multiple communicating pores. Joint pin 7 or can untie-sell 46 through this communicating pores. Auxiliary plate 47 is fixed on the thick wall portion 6 in dish portion 122 by joint pin 7.

Can untie-sell 46

Can untie-sell 46 be the bar-like member of through dish portion 122 and auxiliary plate 47. Can untie-sell 46 can be configured to can move in the axial direction relative to dish portion 122 and auxiliary plate 47. Can untie-sell 46 terminal part be preferably semi-spherical shape. That is, can untie-sell 46 be configured to can move in the axial direction relative to dish portion 122, and through dish portion 122.

Pressing plate 48

The dish portion 122 that pressing plate 48 limits flexible outer rotor 12 is relative to torque transmission member 3 movement in the axial direction. Pressing plate 48 has the toroidal surrounding low-speed rotary shaft 2. Pressing plate 48 can move in the axial direction. That is, torque restricting means 4 has pressing plate 48, and the dish portion 122 that this pressing plate 48 limits flexible outer rotor 12 is relative to torque transmission member 3 movement in the axial direction.

Dish spring 49

Dish spring 49 is can the force application part that exerts a force to torque transmission member 3 side of axis relative to low-speed rotary shaft 2 of untie-sell 46. Dish spring 49 has the shape surrounding low-speed rotary shaft 2, and the stress according to axis produces elasticity distortion. Dish spring 49 is configured between pressing plate 48 and adjustment screw 45, and can untie-sell 46 be exerted a force to axial outgoing side by pressing plate 48. That is, have can the force application part that exerts a force to torque transmission member 3 side of axis relative to low-speed rotary shaft 2 of untie-sell 46 for harmonic gear drive 100.

Recess 31 limit can untie-sell 46 relative to torque transmission member 3 movement in the circumferential. Therefore, in from dish portion 122 to the transmission of torque of torque transmission member 3, transmit the torque being no more than higher limit, cut off the transmission of the torque exceeding higher limit. Namely, as shown in Figure 2 such than rotation center axis J state on the lower, untie-sell 46 side (dish opposed faces 32) of input side of torque transmission member 3 can be climbed up from recess 31 due to torque restricting means 4, it is therefore possible to cause clutch coupling to deviate, flexible outer rotor 12 displacement relatively with the circumference of low-speed rotary shaft 2. That is, hold can the recess 31 of terminal part of untie-sell 46 being had at dish opposed faces 32 place put with dish portion 122 for torque transmission member 3. Recess 31 limit can untie-sell 46 relative to torque transmission member 3 movement in the circumferential. In other words, torque restricting means 4 have restriction can untie-sell 46 relative to the recess 31 of torque transmission member 3 movement in the circumferential. According to this structure, it is possible to easily be set between the dish portion 122 of torque transmission member 3 and flexible outer rotor 12 higher limit of the torque that can transmit. Such as, by regulating the elastic properties of force application part, or change can the terminal part of untie-sell 46 or the shape of recess 31, it is possible to the higher limit of the torque that adjustment easily can be transmitted.

In the harmonic gear drive 100 involved by present embodiment, when low-speed rotary shaft 2 applies excessive revolving force, by the effect of torque restricting means 4, produce to slide between torque transmission member 3 and dish portion 122. Therefore, strengthen with flexible outer rotor 12 wall portion is become thick compared with the situation of intensity, it is possible to do not increase transmission loss, prevent flexible outer rotor 12 from producing viscous deformation or damage for the excessive load inputted by low-speed rotary shaft 2.

In the harmonic gear drive 100 involved by present embodiment, adjustment screw 45, auxiliary plate 47, pressing plate 48 and dish spring 49 are overlapping with the cylindrical portion 121 of flexible outer rotor 12 in the axial direction. Therefore, it is configured at adjustment screw 45, auxiliary plate 47, pressing plate 48 and dish spring 49 than dish portion 122 by compared with being positioned at of outgoing side, or compared with the situation being configured to lean out from cylindrical portion 121, the size of the axis of harmonic gear drive 100 can slimming.

In the harmonic gear drive 100 involved by present embodiment, torque restricting means 4 have adjustment screw 45, can untie-sell 46, auxiliary plate 47, pressing plate 48 and dish spring 49. Therefore, the higher limit of the torque that can transmit that harmonic gear drive 100 is easily set between torque transmission member 3 and dish portion 122.

Such as, by dish spring 49 is changed to the different parts of coefficient of elasticity, or change can the terminal part of untie-sell 46 or the shape of recess 31, it is possible to the higher limit of fine setting torque further.

The structure of torque restricting means 4 is not defined as above-mentioned structure. Such as, it is also possible in the axial direction, torque transmission member 3 is configured at the position leaning on input side than the dish portion 122 of flexible outer rotor 12, and adjustment screw 45, auxiliary plate 47, pressing plate 48 and dish spring 49 are configured at the position leaning on outgoing side than dish portion 122.

In this embodiment, force application part can also whisker for making low-speed rotary shaft 2 through.

The configuration of recess 31 and shape are not defined as above-mentioned content. Such as, it is also possible in torque restricting means 4, recess arrangement in dish portion 122, through torque transmission member 3 the terminal part of untie-sell can be contained in recess.

3rd preferred implementation

Fig. 4 is the sectional view of the configuration example illustrating the harmonic gear drive 100 involved by the 3rd preferred implementation of the present utility model, illustrates the cross section of torque restricting means 4. Cross section when harmonic gear drive 100 cutting being opened by the plane comprising rotation center axis J is shown in the drawings. Figure 4 illustrates, in the position of side more top than rotation center axis J, a part for transmission of torque ball 50 is contained in the state of the recess 31 of torque transmission member 3, and than rotation center axis J position on the lower, transmission of torque ball 50 moves to the state of the position of deviation recess 31.

The difference of the structure of the harmonic gear drive 100 involved by the structure of the harmonic gear drive 100 involved by the 3rd enforcement mode and the 2nd preferred implementation is: have that replace can the transmission of torque ball 50 of untie-sell 46 and auxiliary plate 47. Torque restricting means 4 has adjustment screw 45, pressing plate 48, dish spring 49 and transmission of torque ball 50.

Transmission of torque ball 50

Transmission of torque ball 50 is spherical, and transmits revolving force from dish portion 122 to torque transmission member 3. Dish portion 122 has ball through in the axial direction and holds hole 123. Transmission of torque ball 50 is contained in ball and holds hole 123. Transmission of torque ball 50 is configured to move in the axial direction relative to dish portion 122. That is, transmission of torque ball 50 is contained in the communicating pores in through dish portion 122, and can move in the axial direction relative to dish portion 122.

Pressing plate 48 confinement plate portion 122 is relative to torque transmission member 3 movement in the axial direction. Transmission of torque ball 50 is exerted a force to axial outgoing side by dish spring 49 by pressing plate 48. That is, transmission of torque ball 50 is exerted a force to torque transmission member 3 side of axis by force application part relative to low-speed rotary shaft 2. Torque transmission member 3 has recess 31. Recess 31 is configured at dish portion 122 the dish opposed faces 32 put. Recess 31 holds transmission of torque ball 50 at least partially. Recess 31 torque-limiting transmission ball 50 is relative to torque transmission member 3 movement in the circumferential. In other words, torque restricting means 4 has the recess that torque-limiting transmission ball 50 moves in the circumferential relative to torque transmission member 3. According to this structure, in from dish portion 122 to the transmission of torque of torque transmission member 3, while transmitting the torque being no more than higher limit, and cut off the torque exceeding higher limit. Can easily adjust the higher limit of the torque can transmitted between torque transmission member 3 and dish portion 122.

In the harmonic gear drive 100 shown in Fig. 4, climb up the side (dish opposed faces 32) (illustrated in fig. 4 in the state than rotation center axis J position on the lower) of the input side of torque transmission member 3 due to transmission of torque ball 50 from recess 31, therefore there is the possibility of clutch coupling deviation, flexible outer rotor 12 and the relative displacement of the circumference of low-speed rotary shaft 2.

In the present embodiment, torque restricting means 4 has adjustment screw 45, pressing plate 48, dish spring 49 and transmission of torque ball 50. Therefore, in harmonic gear drive 100, it is easy to ground is set between torque transmission member 3 and dish portion 122 higher limit of the torque that can transmit.

4th preferred implementation

Fig. 5 is the sectional view of the configuration example illustrating the harmonic gear drive 100 involved by the 4th preferred implementation of the present utility model, illustrates the cross section of torque restricting means 4. In the drawings, cross section when harmonic gear drive 100 cutting being opened by the plane comprising rotation center axis J is shown.

The structure of the harmonic gear drive 100 involved by the 4th preferred implementation is compared with the structure of the harmonic gear drive 100 involved by the 3rd preferred implementation, and the structure of torque restricting means 4 is different. Torque restricting means 4 has adjustment screw 45, pressing plate 48, transmission of torque ball 50, whisker 51 and auxiliary plate 52.

Auxiliary plate 52 is the spacer of the toroidal surrounding low-speed rotary shaft 2, and is configured between dish portion 122 and pressing plate 48. Auxiliary plate 52 is fixed on the thick wall portion 6 in dish portion 122 by joint pin 7.

Transmission of torque ball 50 is spherical parts, and transmits revolving force from dish portion 122 to torque transmission member 3. The ball that transmission of torque ball 50 is contained in through dish portion 122 holds in hole 123.

Whisker 51 is the force application part exerted a force to torque transmission member 3 side of axis relative to low-speed rotary shaft 2 by transmission of torque ball 50. Whisker 51 produces elasticity distortion according to the stress of axis. Whisker 51 is contained in the communicating pores of through in the axial direction auxiliary plate 52. The end of the input side of whisker 51 contacts with pressing plate 48. The end of the outgoing side of whisker 51 contacts with transmission of torque ball 50.

Recess 31 torque-limiting transmission ball 50 is relative to torque transmission member 3 movement in the circumferential. Recess 31 in from dish portion 122 to the transmission of torque of torque transmission member 3, while transmitting the torque being no more than higher limit, and cuts off the torque exceeding higher limit.

In the harmonic gear drive 100 involved by present embodiment, climb up the side (dish opposed faces 32) (illustrated in fig. 5 in the state than rotation center axis J position on the lower) of the input side of torque transmission member 3 due to the transmission of torque ball 50 of torque restricting means 4 from recess 31, therefore there is the possibility of clutch coupling deviation, flexible outer rotor 12 and the relative displacement of the circumference of low-speed rotary shaft 2.

In the harmonic gear drive 100 involved by present embodiment, torque restricting means 4 has adjustment screw 45, pressing plate 48, transmission of torque ball 50, whisker 51 and auxiliary plate 52. Therefore, in harmonic gear drive 100, it is easy to ground is set between the dish portion 122 of torque transmission member 3 and flexible outer rotor 12 higher limit of the torque that can transmit.

5th preferred implementation

Fig. 6 is the sectional view of the configuration example illustrating the harmonic gear drive 100 involved by the 5th preferred implementation of the present utility model, illustrates the cross section of torque restricting means 4. Cross section when harmonic gear drive 100 cutting being opened by the plane comprising rotation center axis J is shown in the drawings. Dish portion has multiple protuberance 124. Figure 6 illustrates, in the position of side more top than rotation center axis J, protuberance 124 is contained in the state of recess 31, and than rotation center axis J position on the lower, protuberance 124 moves to the position of deviation recess 31, and the state that the inner peripheral edge portion generation in dish portion 122 is out of shape to the elasticity of input side.

Fig. 7 is the figure observing flexible outer rotor 12 from input side. The seam 125 of two or more it is configured with in the side of the input side in dish portion 122. Seam 125 extends from the inner peripheral edge portion in dish portion 122 to radial outside. Seam 125 configures across constant interval in the circumferential. Thus, the elastic deformation energy in dish portion 122 enough becomes easy. In dish portion 122, it is circumferentially same that the protuberance 124 of two or more is configured at centered by rotation center axis J. Each protuberance 124 configures across constant interval in the circumferential. In dish portion 122 illustrated in fig. 7, the interval configurations such as four protuberances 124.

The structure of the harmonic gear drive 100 involved by the 5th preferred implementation is compared with the structure of the harmonic gear drive 100 involved by the 2nd preferred implementation, and the structure of torque restricting means 4 is different. It is configured with groove 22 in the end of the input side of low-speed rotary shaft 2. Back-up ring 55 described later is contained in groove 22. Groove 22 is the recess surrounding low-speed rotary shaft 2.

Torque restricting means 4 has pressing plate 53. Pressing plate 53 confinement plate portion 122 is relative to torque transmission member 3 movement in the axial direction. Recess 31, pressing plate 53 and back-up ring 55 that torque restricting means 4 has the protuberance 124 being arranged at dish portion 122, is arranged at torque transmission member 3.

Dish portion 122 has protuberance 124 outstanding to torque transmission member 3 side in the axial direction. Recess 31 is configured at dish opposed faces 32 and holds protuberance 124. Recess 31 limits protuberance 124 relative to torque transmission member 3 movement in the circumferential. That is, torque transmission member 3 has, with dish portion 122, the dish opposed faces 32 put is being held the recess 31 of protuberance 124. Such as, what two or more protuberance 124 was configured at centered by rotation center axis J is circumferentially same. Each protuberance 124 configures across constant interval in the circumferential.

Pressing plate 53 has the toroidal surrounding low-speed rotary shaft 2. Accommodation section 54 is configured with accommodation section 54 at the outgoing side of pressing plate 53. Accommodation section 54 holds and occurs elasticity to be out of shape and move to the inner peripheral edge portion in the dish portion 122 of input side. Pressing plate 53 limits the movement to axial input side by the back-up ring 55 being contained in groove 22.

Climb up the side (dish opposed faces 32) (state than rotation center axis J position on the lower illustrated in fig. 6) of the input side of torque transmission member 3 due to protuberance 124 from recess 31, therefore there is the possibility of clutch coupling deviation, flexible outer rotor 12 and the relative displacement of the circumference of low-speed rotary shaft 2.

In the present embodiment, torque restricting means 4 has pressing plate 53, the protuberance 124 in dish portion 122 and the recess 31 of torque transmission member 3. Therefore, can to become structure simple for torque restricting means 4, it is easy to manufactures harmonic gear drive 100. Owing to inhibiting increasing of the part number of harmonic gear drive 100, therefore, it is possible to reduce manufacturing cost.

Protuberance 124 is not defined as above-mentioned content with the configuration of recess 31. Such as, it is also possible to by recess arrangement in the dish portion 122 of flexible outer rotor 12, protuberance is configured at the dish opposed faces 32 of torque transmission member 3. At this moment, protuberance is contained in the recess in dish portion 122.

In the enforcement mode of first to the 5th, flexible outer rotor 12 has the parts having end drum. In following the 6th, the 7th preferred implementation being described, flexible outer rotor 12 has the parts of drum, and the parts of this drum have the dish portion 122 along shape in the end of outgoing side.

6th preferred implementation

Fig. 8 is the sectional view of the configuration example illustrating the harmonic gear drive 100 involved by the 6th preferred implementation of the present utility model, illustrates cross section when harmonic gear drive 100 cutting being opened by the plane comprising rotation center axis J. In fig. 8, using the right side of accompanying drawing as input side, using left side as outgoing side, draw the harmonic gear drive 100 that torque restricting means 4 is configured at outgoing side.

Harmonic gear drive 100 has step-down gear 1, torque transmission member 3, torque restricting means 4, low-speed rotary shaft 8 and crossed roller bearing 9. The flexible outer rotor 12 of step-down gear 1 is the parts of drum. For being configured at the end of the outgoing side of flexible outer rotor 12 along the dish portion 122 of shape. Flexible outer rotor 12 has the cylindrical portion 121 and dish portion 122 that extend vertically. Dish portion 122 extends from the end of the outgoing side of cylindrical portion 121 to radial outside. Therefore, dish portion 122 has the toroidal extended from one end of cylindrical portion 121 to radial outside.

The external tooth form of flexible outer rotor 12 is formed in the end of the input side of cylindrical portion 121. Dish portion 122 is toroidal. The peripheral edge portion of cylindrical portion 121 has the axial thickness thick wall portion 6 thicker than the axial thickness in other region. In dish portion 122, the periphery of thick wall portion 6 and the inner peripheral surface of low-speed rotary shaft 8 are to putting.

The rigid convex wheel plate 132 of wave producer 13 has communicating pores 1323. Distribution cable etc. is such as had to pass at communicating pores 1323. Low-speed rotary shaft 8 is the parts of the low speed rotation centered by rotation center axis J. Low-speed rotary shaft 8 and rigid internal gear 11 arranged coaxial, and the revolving force of output speed reducer 1.

Low-speed rotary shaft 8 is drum, and surrounds step-down gear 1 and torque restricting means 4. Low-speed rotary shaft 8 has flange side component 81 and step-down gear side component 82. Low-speed rotary shaft 8 has open holes 83 through in the axial direction. Flange side component 81 is by open holes 83 and is connected with step-down gear side component 82 by bolt 84. In other words, in low-speed rotary shaft 9, it is possible to by open holes 83, the object parts as load are installed.

In the present embodiment, harmonic gear drive 100 has crossed roller bearing 9. Crossed roller bearing 9 is for being configured at the radial outside of rigid internal gear 11, and relative to rigid internal gear 11, low-speed rotary shaft 8 is supported the bearing for rotating. Crossed roller bearing 9 is the roller bearing making roller cross-over configuration between inner ring and outer ring. Crossed roller bearing 9 at least supports the side in axial load or radial load. Crossed roller bearing 9 is configured between the step-down gear side component 82 of low-speed rotary shaft 8 and rigid internal gear 11.

Torque transmission member 3

The revolving force of flexible outer rotor 12 is passed to low-speed rotary shaft 8 by torque transmission member 3. Torque transmission member 3 is the toroidal extended from the inner peripheral surface of low-speed rotary shaft 8 to radially inner side. With dish portion 122 in the axial direction to the position put, torque transmission member 3 is fixed on low-speed rotary shaft 8. Such as, torque transmission member 3 is made up of circular plate member. Preferred torque transmission member 3 forms as one with the flange side component 81 of low-speed rotary shaft 8. That is, torque transmission member 3 has the toroidal extended from the inner peripheral surface of low-speed rotary shaft 8 to radially inner side.

Torque restricting means 4

Torque restricting means 4 is the clutch coupling of friction formula, and have pressing plate 43, dish spring 44 and from the one of axial holding tray portion, both sides 122 to friction plate 41,42. Pressing plate 43 and dish spring 44 are configured at the position of the other end side leaning on cylindrical portion 121 than dish portion 122 in the axial direction. That is, pressing plate 43 and dish spring 44 are configured at the other end side of the cylindrical portion 121 of input side. In more detail, pressing plate 43 and dish spring 44 are configured at the position leaning on side, dish portion 122 than the end of input side. Pressing plate 43 and dish spring 44 are configured at the radial outside of cylindrical portion 121. That is, the force application part of torque restricting means 4 is configured at the radial outside of cylindrical portion 121. According to this structure, owing to the space of the radially inner side of cylindrical portion 121 can be guaranteed, accordingly, it may be possible to expand the scope of design.

Friction plate 41,42

Friction plate 41,42 has toroidal, and controls to transmit the higher limit of torque. Friction plate 41 is configured between torque transmission member 3 and dish portion 122. The side of the input side of friction plate 41 contacts with thick wall portion 6. The side of the outgoing side of friction plate 41 contacts with torque transmission member 3. Friction plate 42 is configured between dish portion 122 and pressing plate 43. The side of the outgoing side of friction plate 42 contacts with thick wall portion 6. The side of the input side of friction plate 42 contacts with pressing plate 43. Friction plate 41,42 is fixed on torque transmission member 3 by spline pin 85 through in the axial direction. Thus, prevent the position of the circumference of the low-speed rotary shaft 8 relative to friction plate 41,42 from producing deviation.

Pressing plate 43

The dish portion 122 that pressing plate 43 limits flexible outer rotor 12 is relative to torque transmission member 3 movement in the axial direction. Pressing plate 43 has the toroidal of the cylindrical portion 121 surrounding flexible outer rotor 12.

Dish spring 44

Dish spring 44 is the force application part exerted a force to torque transmission member 3 side of axis relative to low-speed rotary shaft 8 in dish portion 122. Dish spring 44 has the shape of the cylindrical portion 121 surrounding flexible outer rotor 12, and the stress according to axis produces elasticity distortion. Dish spring 44 is configured at the radial outside of cylindrical portion 121. Dish spring 44 is configured at the position leaning on side, dish portion 122 than crossed roller bearing 9 in the axial direction. More specifically, dish spring 44 is configured between the outgoing side side of pressing plate 43 and step-down gear side component 82, and by pressing plate 43 to axial outgoing side force. That is, force application part is configured at the position leaning on side, dish portion 122 than crossed roller bearing 9 in the axial direction. According to this structure, it is possible to the axial length of harmonic reduction wheelwork 100.

In the harmonic gear drive 100 involved by present embodiment, torque below the value of setting device damage, when inputting excessive revolving force by low-speed rotary shaft 8, produce between torque transmission member 3 and dish portion 122 to slide by acting on of torque restricting means 4. Therefore, harmonic gear drive 100 can prevent flexible outer rotor 12 from the excessive revolving force inputted by low-speed rotary shaft 8 is produced to viscous deformation or damage. For harmonic gear drive 100 involved in this enforcement mode, compared with the situation becoming thick with the wall thickness making flexible outer rotor 12 and gain in strength, it is possible to suppress to transmit the increase of loss.

In the present embodiment, torque restricting means 4 is configured between flexible outer rotor 12 and low-speed rotary shaft 8. Therefore, it is possible to avoid flexible outer rotor 12 to damage. Therefore, flexible outer rotor 12 can slimming further. Its result is, harmonic gear drive 100, owing to can reduce the resistance to deformation of flexible outer rotor 12, transmits loss therefore, it is possible to reduce.

In the present embodiment, pressing plate 43 and dish spring 44 configure with cylindrical portion 121 in the axial direction with repeating. Therefore, leaning on the position of outgoing side to compare with pressing plate 43 and dish spring 44 being configured at than the dish portion 122 of flexible outer rotor 12, and the situation from cylindrical portion 121 leans out that is configured to is compared, the axial size of harmonic gear drive 100 can slimming.

7th preferred implementation

In the 7th preferred implementation, torque restricting means 4 has engaged clutch.

Fig. 9 is the sectional view of the configuration example illustrating the harmonic gear drive 100 involved by the 7th preferred implementation of the present utility model, illustrates the cross section of torque restricting means 4. Cross section when harmonic gear drive 100 cutting being opened by the plane comprising rotation center axis J is shown in the drawings. Figure 9 illustrates, than rotation center axis J position on the lower, the protuberance 126 in dish portion 122 is contained in the state of the recess 31 of torque transmission member 3, and the position in side more top than rotation center axis J, protuberance 126 moves to the position of deviation recess 31, and the peripheral edge portion in dish portion 122 produces the state of viscous deformation to input side.

The structure of the harmonic gear drive 100 involved by the 7th preferred implementation is compared with the structure of the harmonic gear drive 100 involved by the 6th preferred implementation, and the structure of torque restricting means 4 is different. Torque restricting means 4 has pressing plate 56, whisker 57, the protuberance 126 being arranged at dish portion 122, the recess 31 that is arranged at torque transmission member 3. The dish portion 122 of the flexible outer rotor 12 of restriction is relative to torque transmission member 3 movement in the axial direction. That is, torque restricting means 4 has pressing plate 56, and the dish portion 122 that this pressing plate 56 limits flexible outer rotor 12 is relative to torque transmission member 3 movement in the axial direction.

Protuberance 126 is protuberance outstanding to torque transmission member 3 side in the axial direction. Recess 31 is configured at dish opposed faces 32, and holds protuberance 126. Recess 31 limits protuberance 126 relative to torque transmission member 3 movement in the circumferential. Such as, what the protuberance 126 of two or more was configured at centered by rotation center axis J is circumferentially same. Each protuberance 126 configures across constant interval in the circumferential.

Pressing plate 56 has the toroidal surrounding cylindrical portion 121. Whisker 57 is the force application part exerted a force to axial torque transferring elements 3 side relative to low-speed rotary shaft 8 by pressing plate 56, and whisker 57 produces elasticity distortion according to the stress of axis. The step-down gear side component 82 of low-speed rotary shaft 8 has spring and holds cave 821. Whisker 57 is configured in spring to be held in cave 821.

In fig .9, protuberance 126 climbs up the side (dish opposed faces 32) of the input side of torque transmission member 3 from recess 31. Thus (state of side more top than rotation center axis J illustrated in fig. 9), there is the possibility of the relative displacement of the circumference of clutch coupling deviation, flexible outer rotor 12 and low-speed rotary shaft 8.

In the harmonic gear drive 100 involved by present embodiment, pressing plate 56 and whisker 57 are overlapping with cylindrical portion 121 in the axial direction. Therefore, harmonic gear drive 100 is being configured at the position leaning on outgoing side than dish portion 122 with pressing plate 56 and whisker 57, or compares when configuring with leaning out from cylindrical portion 121, and the axial size of harmonic gear drive 100 can slimming.

In addition, the utility model also can be applicable to such as low-speed rotary shaft 2 and be fixed on shell, and exported the harmonic gear drive of the rotary motion of electronic motor by rigid internal gear 11.

Claims

1. a harmonic gear drive, described harmonic gear drive has:

The rigid internal gear of ring-type;

Flexible outer rotor, described flexible outer rotor is ring-type, and is configured at the radially inner side of described rigid internal gear; And

Wave producer, described wave producer is configured at the radially inner side of described flexible outer rotor, and compared with described flexible outer rotor, it is possible to high speed rotating relatively,

Make described flexible outer rotor bending diametrically by described wave producer and with the engaging of described rigid internal gear local, and engagement position is moved in the circumferential, thus make the described rigid internal gear low speed rotation relatively with described flexible outer rotor that there is number of teeth difference

Described harmonic gear drive is characterised in that,

Described flexible outer rotor has:

Cylindrical portion, described cylindrical portion extends vertically; And

Dish portion, described dish portion radially extends from one end of described cylindrical portion,

Described harmonic gear drive has:

Low-speed rotary shaft;

Torque transmission member, the position put is being fixed in described low-speed rotary shaft with described dish portion by described torque transmission member in the axial direction; And

Torque restricting means, described torque restricting means limits from described dish portion to the transmission of the torque of described torque transmission member.

2. harmonic gear drive according to claim 1, it is characterised in that,

Described torque restricting means has:

One pair of friction plate, friction plate is kept described dish portion from axial both sides by described one; And

Force application part, described dish portion is exerted a force by described force application part in the axial direction towards described torque transmission member.

3. harmonic gear drive according to claim 2, it is characterised in that,

Described force application part is configured at the position of the other end side leaning on described cylindrical portion in the axial direction than described dish portion.

4. harmonic gear drive according to claim 3, it is characterised in that,

Described dish portion has the toroidal extended from one end of described cylindrical portion to radially inner side,

The described force application part of described torque restricting means is configured at the radially inner side of described cylindrical portion.

5. harmonic gear drive according to claim 3, it is characterised in that,

Described dish portion has the toroidal extended from one end of described cylindrical portion to radial outside,

The described force application part of described torque restricting means is configured at the radial outside of described cylindrical portion.

6. harmonic gear drive according to claim 5, it is characterised in that,

Described harmonic gear drive has:

Crossed roller bearing, described crossed roller Bearing configuration is in the radial outside of described rigid internal gear, and supports described low-speed rotary shaft for rotating relative to described rigid internal gear,

Described torque transmission member has the toroidal extended from the inner peripheral surface of described low-speed rotary shaft to radially inner side,

Described force application part is configured in the axial direction than the position of side, dish portion described in described crossed roller Bearing support.

7. harmonic gear drive according to claim 1, it is characterised in that,

Described torque restricting means has:

Pressing plate, the described dish portion of the described flexible outer rotor of described pressing plate restriction moves in the axial direction relative to described torque transmission member;

Can untie-sell, described can untie-sell be configured to can move in the axial direction relative to dish portion, and through described dish portion; And

Force application part, described force application part by described can untie-sell axial relative to described low speed rotation described torque transmission member side force,

Described torque transmission member has recess, and described recess can the terminal part of untie-sell be contained in described dish portion the dish opposed faces put by described, can untie-sell move in the circumferential relative to described torque transmission member described in the restriction of described recess.

8. harmonic gear drive according to claim 7, it is characterised in that,

The described pressing plate of described torque restricting means and described force application part are configured at the radially inner side of described cylindrical portion.

9. harmonic gear drive according to claim 1, it is characterised in that,

Described torque restricting means has:

Transmission of torque ball, described transmission of torque ball is contained in the communicating pores in through described dish portion, and can move in the axial direction relative to described dish portion; And

Force application part, described torque transmission member side axial relative to described low speed rotation for described transmission of torque ball is exerted a force by described force application part,

Described torque transmission member has recess, and a part for described transmission of torque ball is contained in described dish portion to the dish opposed faces put by described recess, and described recess limits described transmission of torque ball and moves in the circumferential relative to described torque transmission member.

10. harmonic gear drive according to claim 9, it is characterised in that,

11. harmonic gear drives according to the arbitrary item in claim 2 to 10, it is characterised in that,

Described force application part is made up of dish spring or whisker.

12. harmonic gear drives according to claim 1, it is characterised in that,

Described torque restricting means has pressing plate, and the described dish portion of the described flexible outer rotor of described pressing plate restriction moves in the axial direction relative to described torque transmission member,

Described dish portion has protuberance, and described protuberance is outstanding to described torque transmission member side in the axial direction,

Described torque transmission member has recess, and described protuberance is contained in described dish portion to the dish opposed faces put by described recess, and described recess limits described protuberance and moves in the circumferential relative to described torque transmission member.

13. 1 kinds of harmonic gear drives have:

The rigid internal gear of ring-type;

The number of teeth of described rigid internal gear is different from the number of teeth of described flexible outer rotor,

Described flexible outer rotor locally engages with described rigid internal gear, and bends diametrically relative to described rigid internal gear,

Described rigid internal gear and described flexible outer rotor relative to described wave producer can low speed rotation,

Described harmonic gear drive is characterised in that,

Described flexible outer rotor has:

Cylindrical portion, described cylindrical portion extends vertically; And

Described harmonic gear drive has:

Low-speed rotary shaft;

Torque restricting means, described torque restricting means contacts with described torque transmission member.

14. harmonic gear drives according to claim 13, it is characterised in that,

Described torque restricting means has:

15. harmonic gear drives according to claim 14, it is characterised in that,

16. harmonic gear drives according to claim 15, it is characterised in that,

17. harmonic gear drives according to claim 15, it is characterised in that,

18. harmonic gear drives according to claim 17, it is characterised in that,

Described harmonic gear drive has:

19. harmonic gear drives according to claim 13, it is characterised in that,

Described torque restricting means has:

Can untie-sell, described can untie-sell be configured to can move in the axial direction relative to dish portion, and through described dish portion;

Force application part, described force application part by described can untie-sell axial relative to described low speed rotation described torque transmission member side force; And

Recess, can move relative to described torque transmission member described in the restriction of described recess in the circumferential in untie-sell,

Described torque transmission member can the terminal part of untie-sell be contained in described with described dish portion the dish opposed faces put.

20. harmonic gear drives according to claim 19, it is characterised in that,

21. harmonic gear drives according to claim 13, it is characterised in that,

Described torque restricting means has:

Transmission of torque ball, described transmission of torque ball is contained in the communicating pores in through described dish portion, and can move in the axial direction relative to described dish portion;

Force application part, described torque transmission member side axial relative to described low speed rotation for described transmission of torque ball is exerted a force by described force application part; And

Recess, described recess limits described transmission of torque ball and moves in the circumferential relative to described torque transmission member,

A part for described transmission of torque ball is contained in described dish portion the dish opposed faces put by described torque transmission member.

22. harmonic gear drives according to claim 21, it is characterised in that,

23. according to claim 14 to the harmonic gear drive described in the arbitrary item in 22, it is characterised in that,

Described force application part is made up of dish spring or whisker.

24. harmonic gear drives according to claim 13, it is characterised in that,