JP3882167B2 - Backlash-less gear transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a backlashless gear transmission, and more particularly to a backlashless gear transmission using a one-way clutch.
[0002]
[Prior art]
Gear play (hereinafter referred to as backlash) in the speed reducer is a necessary element for the following reasons. In other words, assembly and production tolerances are necessary to engage gears with different numbers of teeth, so a backlash is provided in the speed reducer design as an appropriate play, and production errors and the like are absorbed by this backlash. As a result, the gears are deeply engaged with each other when the gears are engaged, and destruction due to excessive pressure and force is avoided. However, this backlash also causes the following adverse effects.
[0003]
1) Due to the occurrence of rotational play due to backlash at the final stage, a deviation occurs immediately after the start of transmission at the input angle and the output angle.
[0004]
2) The meshing gap due to backlash also causes noise during rotation.
[0005]
3) When torque and rotation angle control are performed by a stepping motor and a motor by closed loop control, the combination with a speed reducer with backlash results in a significant loss of control range.
[0006]
Currently, there are the following three types of methods for solving this problem as a backlash-less mechanism for a speed reducer.
[0007]
1) Increase the meshing rate of meshing gears. (Including a reduction mechanism using a ball, conical roller, etc. without using gears, such as a harmonic reduction).
[0008]
2) A mechanism combining a gear and a spring.
[0009]
3) Minimization of backlash by high precision gear, mechanism using conical gear.
[0010]
However, the above is complicated in structure, is constituted by expensive gears, etc., and cannot cope with high loads.
[0011]
A backlashless device for light load is known (Patent Document 1).
[0012]
[Patent Document 1]
Japanese Utility Model Laid-Open No. 2-134351 (pages 7 to 11, FIG. 1).
[0013]
[Problems to be solved by the invention]
In such a conventional apparatus, one gear is divided into two vertically and divided into a main gear and a sub-gear, and the main and sub-gears are engaged with a phase shifted via an elastic member. . However, in this case, the manufacturing process accuracy is required and suitable for light loads, but remains unsuitable for heavy loads.
[0014]
The present invention is intended to eliminate such drawbacks.
[0015]
[Means for Solving the Problems]
The backlashless gear transmission of the present invention includes a reversible motor gear, a forward rotation pinion and a reverse rotation pinion that are arranged on both upper sides of the motor gear and have the same number of teeth that mesh with the motor gear, respectively. Fixed to the support shaft of the diversion pinion, and fixed to the forward rotation intermediate gear for transmitting the normal rotation of the normal rotation pinion via the one-way clutch for normal rotation, and to the support shaft of the reverse rotation pinion, A reverse rotation intermediate gear having the same number of teeth as the forward rotation intermediate gear, in which the reverse rotation of the reverse rotation pinion is transmitted via the reverse rotation one-way clutch, and an output gear meshing with these intermediate gears on both lower sides thereof. When, the forward rotation and become more and forward side and reverse side spring means for backlash absorbing reverse rotation pinion, the forward side spring means, the support shaft of the forward rotation pinion Winding a helical spring which is wound, one end of which is fixed to the forward rotation pinion, the other end is fixed to the support shaft of the forward rotation pinion, is the reverse side spring means, the support of the reversing pinions A helical spring wound around a shaft, one end of which is fixed to the reversing pinion and the other end is fixed to the supporting shaft of the reversing pinion.
[0016]
The backlashless gear transmission of the present invention includes a reversible motor gear, a forward rotation pinion and a reverse rotation pinion that are arranged on both upper sides of the motor gear and have the same number of teeth that mesh with the motor gear, respectively. Fixed to the support shaft of the diversion pinion, and fixed to the forward rotation intermediate gear for transmitting the normal rotation of the normal rotation pinion via the one-way clutch for normal rotation, and to the support shaft of the reverse rotation pinion, A reverse rotation intermediate gear having the same number of teeth as the forward rotation intermediate gear, in which the reverse rotation of the reverse rotation pinion is transmitted via the reverse rotation one-way clutch, and an output gear meshing with these intermediate gears on both lower sides thereof. And forward and reverse spring means for absorbing backlash of the forward and reverse pinions, and the forward spring means is a leaf spring, one end of which is Is fixed to the forward rotation pinion, the other end is fixed to the support shaft of the forward rotation pinion After curved over substantially 180 ° along the peripheral surface of the support shaft of the forward rotation pinion, is the reverse side spring means A leaf spring, one end of which is fixed to the reversing pinion, and the other end is bent over the outer peripheral surface of the supporting shaft of the reversing pinion over approximately 180 ° and then fixed to the supporting shaft of the reversing pinion It is characterized by being.
[ 0017 ]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[ 0018 ]
As shown in FIG. 1, the backlashless gear transmission according to the first embodiment of the present invention includes a motor gear 1 that is directly connected to an output shaft of a reversible motor, and a motor gear 1 that is disposed on both upper sides of the motor gear 1. Forward and reverse pinions 2 and 3 having the same number of teeth meshing with each other, intermediate gears 4 and 5 directly connected to the support shafts of these pinions 2 and 3, and these intermediate gears 4 and 5 meshing on both lower sides thereof 1 and a large-diameter output gear 6 that rotates in the counterclockwise direction of the forward rotation pinion 2 through a one-way clutch 8 and a support shaft 7a as shown in FIGS. A coil spring 9 is wound around the support shaft 7a of the forward rotation pinion 2, the one end 9a of the spring 9 is fixed to the pinion 2, and the other end 9b is fixed to the support shaft. 7a and the pinion 2 is shown in FIG. The spring 9 is in the tightened so when rotating counterclockwise are.
[ 0019 ]
In addition, the clockwise rotation of the reverse pinion 3 is transmitted to the intermediate gear 5 via the one-way clutch 10 and the support shaft 7b as shown in FIG. When the coil spring 11 is wound around the support shaft 7b, one end 11a of the spring 11 is fixed to the pinion 3, the other end 11b is fixed to the support shaft 7b, and the pinion 3 rotates clockwise in FIG. The spring 11 is tightened.
[ 0020 ]
Reference numeral 12 denotes a hub fixed to the outer periphery of the support shafts 7a and 7b with a key or a screw, and 13 denotes a bearing of the support shafts 7a and 7b.
[ 0021 ]
Since the backlash-less gear transmission of the present invention is configured as described above, when the motor gear 1 rotates in the forward direction (clockwise), the teeth 2a on the downstream side in the rotation direction of the forward rotation pinion 2 as shown in FIG. Is pushed by the teeth 1a on the downstream side of the motor gear 1 to rotate the forward rotation pinion 2 counterclockwise, and the output gear 6 meshing with the pinion 2 rotates clockwise to transmit power. At this time, the spring 9 provided in the pinion 2 is in a form in which the spring is tightened, and the backlash is absorbed. Further, the spring 11 provided on the reverse rotation pinion 3 is loosened so that the teeth 3 a on the upstream side of the reverse rotation pinion 3 come into contact with the teeth 1 b on the upstream side of the motor gear 1.
[ 0022 ]
When the motor gear 1 rotates in the reverse direction (counterclockwise), the teeth 3a on the downstream side of the pinion 3 for reverse rotation are pushed by the teeth 1b on the downstream side of the motor gear 1 as shown in FIG. The pinion 3 rotates in the clockwise direction, and the output gear 6 engaged therewith rotates in the counterclockwise direction to transmit power. At this time, the spring 11 shown in FIG. 4 provided in the pinion 3 is tightened, and the backlash is absorbed. Further, at this time, the spring 9 shown in FIG. 3 provided on the forward rotation pinion 2 is loosened so that the teeth 2 a on the upstream side of the forward rotation pinion 2 are in contact with the teeth 1 a on the upstream side of the motor gear 1. Become.
[ 0023 ]
As described above, according to the embodiment of the present invention, the power transmission path at the time of forward rotation and at the time of reverse rotation is divided into two systems, each having the same reduction ratio, and becomes the motor gear and the intermediate gear for forward rotation and reverse rotation. Power transmission with the pinion is performed through a one-way clutch and a spring so that the meshing tooth surfaces in the respective dedicated paths are always in contact with each other, so that the backlash can be extremely easily and reliably reduced.
[ 0024 ]
Any elastic means may be used as long as it has directionality instead of the springs 9 and 11.
[ 0025 ]
One end 14a as shown in FIG. 6 instead of using a helical spring in the first embodiment is fixed to the supporting shaft 7a or 7b in the second embodiment of the present invention, the other end 14b supporting shaft 7a or A leaf spring 14 fixed to the pinion 2 or 3 is used after being bent along the outer peripheral surface of 7b by about 180 °.
[ 0026 ]
The function and effect in this case are the same as in the first embodiment.
[ 0027 ]
【The invention's effect】
As described above, according to the backlashless gear transmission of the present invention, since the tooth surfaces of the gears that are always meshed with each other are brought into contact with each other by a spring, it is very easy to minimize backlash even at high loads. There is a great effect.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a backlashless gear transmission in a first embodiment of the present invention during normal rotation.
FIG. 2 is a side view of a pinion portion for forward rotation of the apparatus shown in FIG.
3 is a longitudinal front view of the pinion portion shown in FIG. 2. FIG.
4 is a longitudinal front view of a reverse pinion portion of the apparatus shown in FIG. 1; FIG.
FIG. 5 is an explanatory diagram at the time of reverse rotation of the backlash-less gear transmission according to the first embodiment of the present invention.
FIG. 6 is an explanatory diagram of spring means in the second embodiment of the present invention.
[Explanation of symbols]
1 motor gear 1a tooth 1b tooth 2 pinion 2a tooth 2b tooth 3 pinion 3a tooth 3b tooth 4 intermediate gear 5 intermediate gear 6 output gear 7a support shaft 7b support shaft 8 one-way clutch 9 helical spring 9a one end 10 one-way clutch 11 helical winding Spring 11a One end 11b The other end 12 Hub 13 Bearing 14 Leaf spring 14a One end 14b The other end

Claims (2)

A reversible motor gear (1) and a forward rotation pinion (2) and a reverse rotation pinion (3) arranged on both sides of the motor gear (1) and having the same number of teeth meshing with the motor gear (1), respectively. When, the forward rotation pinion is fixed to the support shaft (7 a) of (2), forward rotation intermediate the forward rotation of the forward rotation pinion (2) is transmitted via the forward rotation one-way clutch (8) The gear (4) is fixed to the support shaft (7b) of the reverse pinion (3), and the reverse rotation of the reverse pinion (3) is transmitted via the reverse one-way clutch (10). A reverse intermediate gear (5) having the same number of teeth as the forward rotation intermediate gear (4), an output gear (6) meshed with the intermediate gears (4, 5) on both lower sides thereof, Absorbing backlash of diversion and reverse pinions (2, 3) Forward and become more and reverse side spring means (9, 11), the forward side spring means (9), the normal rotation pinion (2) wound helical spring on the support shaft (7a) of the One end of which is fixed to the forward rotation pinion (2), the other end is fixed to the support shaft (7a) of the forward rotation pinion (2), and the reverse spring means (11) is A helical spring wound around the support shaft (7b) of the reverse rotation pinion (3), one end of which is fixed to the reverse rotation pinion (3) and the other end is the support shaft of the reverse rotation pinion (3). A backlashless gear transmission characterized by being fixed to (7b). A reversible motor gear (1) and a forward rotation pinion (2) and a reverse rotation pinion (3) arranged on both sides of the motor gear (1) and having the same number of teeth meshing with the motor gear (1), respectively. When, the forward rotation pinion is fixed to the support shaft (7 a) of (2), forward rotation intermediate the forward rotation of the forward rotation pinion (2) is transmitted via the forward rotation one-way clutch (8) The gear (4) is fixed to the support shaft (7b) of the reverse pinion (3), and the reverse rotation of the reverse pinion (3) is transmitted via the reverse one-way clutch (10). A reverse intermediate gear (5) having the same number of teeth as the forward rotation intermediate gear (4), an output gear (6) meshed with the intermediate gears (4, 5) on both lower sides thereof, Absorbing backlash of diversion and reverse pinions (2, 3) More become a forward side and reverse side spring means (14) of said forward side spring means (14) is a leaf spring, one end of which is fixed to the forward rotation pinion (2), the other end the The reverse-rotation side spring means is fixed to the support shaft (7a) of the forward rotation pinion (2) after being bent over approximately 180 ° along the outer peripheral surface of the support shaft (7a) of the forward rotation pinion (2). (1 4 ) is a leaf spring, one end of which is fixed to the reversing pinion (3) and the other end is approximately 180 ° along the outer peripheral surface of the support shaft (7b) of the reversing pinion (3). A backlashless gear transmission characterized by being fixed to the support shaft (7b) of the reversing pinion (3) after being bent over a distance.

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