JP2518808Y2 - Slip mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a slip mechanism suitable for, for example, a motor with a gear mechanism.

(Prior Art) For example, when a load is driven by a motor with a reduction gear train, if the load side is forcibly rotated by an external force, the motor is overloaded. As a general means for protecting the motor and the internal mechanism from such an overload, it is known to provide a slip mechanism in the power transmission mechanism from the motor to the output shaft.

As a technique for increasing the torque and increasing the reliability of the slip mechanism, it is known that multiple friction plates constituting the friction transmission mechanism are used for automobile clutches and the like. The slip mechanism of the small electric motor described in Japanese Utility Model Publication No. 1-35808 is one of them. FIG. 13 shows the slip mechanism described in the above publication, in which a step portion is formed by forming a shaft end portion 86 having a small diameter oval cross section on the rotary shaft 85.
87, and the friction plate 88, the gear 89, and the friction plate on the shaft end portion 86.
90, the gear 91 is fitted in this order, and further the leaf spring 92 is fitted,
The friction plate 88, the gear 89, the friction plate 90, and the gear 91 are connected to the step portion 87.
And a leaf spring 92 with a predetermined urging force. The shaft holes of the gears 89, 91 are circular with respect to the shaft end portion 86 having the oval cross section, and the gears 89, 91 are fitted so as to be rotatable relative to the rotary shaft 85. On the other hand, the shaft holes of the friction plates 88 and 90 have an oval shape which is the same as the sectional shape of the shaft end portion 86, so that the friction plates 88 and 90 rotate together with the rotary shaft 85. The gears 89, 91 are divided into two, which should originally constitute one gear, and both have the same diameter and the same number of teeth.

When the rotary shaft 85 rotates, the friction plates 88 and 90 rotate together,
The gears 89, 91 are rotationally driven by the frictional force between the friction plate 88, the gear 89, the friction plate 90 and the gear 91. Another gear meshes with the gears 89 and 91, and the rotational force is transmitted.

(Problems to be Solved by the Invention) According to the slip mechanism described in the above publication, the gear is divided into multiple plates, and the friction plates are interposed between the gears and between the gears and the step portion of the rotary shaft. Therefore, it is necessary to provide a gap between the gears, and the effective thickness of the meshing parts of the gears decreases as the number of gears increases to achieve higher torque and higher reliability. However, there is a drawback that the wear resistance and strength are reduced. In addition, wear powder generated at the meshing part may enter the sliding part with the friction plate from the gap between the gears to deteriorate the characteristics, the friction coefficient of each gear may be varied, and the gears may be misaligned in the rotational direction. There is also a drawback that torque variation occurs every time, and the torque tends to concentrate on a part.

The present invention has been made in order to solve the problems of the prior art.The gear itself is an integrated gear without multiple plates, and only the slip part is multiple plates to achieve high torque and high reliability. It is an object of the present invention to provide a slip mechanism that has improved properties.

(Means for Solving the Problems) According to the present invention, gears are concentrically and relatively rotatably fitted on the outer periphery of a rotary member, and a plurality of rotary member-side friction plates that rotate integrally with the rotary member are provided on the rotary member. And a gear-side friction plate that engages with an engaging portion formed on the gear and rotates integrally with the gear is fitted to the rotating member, and the gear, the rotating member-side friction plate, and the gear-side friction plate A regulating portion is formed on the rotating member to regulate the movement in the rotation axis direction, and the gear, the rotating member side friction plate and the gear side friction plate are rotated so as to be sandwiched between them by a predetermined biasing force. A biasing member is attached to the member, and the rotary member side friction plate and the gear side friction plate are alternately stacked.

(Operation) When the gear is rotationally driven, the gear-side friction plate integrally rotates, and the rotational force of the gear-side friction plate is transmitted to the plurality of rotating-member-side friction plates by frictional force, so that the rotating-member-side friction plate is The rotary member is driven to rotate, and the rotary member rotates integrally with the friction plate on the rotary member side. The gear side may be the drive side and the rotating member side may be the load side. In any case, the friction transmission mechanism including the gear side friction plate and the rotating member side friction plate transmits the rotational force. Since the friction transmission mechanism is also a slip mechanism, when an overload is applied to the load side and a certain torque or more is applied to the friction transmission mechanism, slippage occurs in the slip mechanism and an excessive force is applied to the drive side, for example, a motor. To prevent it.

(Example) Hereinafter, an example of a slip mechanism according to the present invention will be described with reference to the drawings.

In FIG. 1 and FIG. 2, the rotary member 1 formed in a shaft shape has a shaft end 3 having a small diameter at the lower end side, and the shaft end 3 having a small diameter is formed to form a stepped regulation. The part 2 is formed. The small-diameter shaft end has a D-shaped cross section by forming a flat surface 4 on its side surface. The shaft end 3 of the small diameter has the shaft hole 21 of the friction plate 11, the shaft hole 22 of the friction plate 12, the shaft hole 23 of the friction plate 13, the shaft hole 8 of the gear 5, and the shaft hole 10 of the biasing member 9 in this order. Penetrates. The friction plates 11 and 13 constitute a rotary member side friction plate, and the shaft holes 21 and 23 thereof are formed in the same D shape as the sectional shape of the shaft end portion 3 and have the same size. By being formed, it is adapted to rotate integrally with the rotating member 1. On the other hand, the friction plate 12 constitutes a gear-side friction plate, the shaft hole 22 of which has a circular shape and is rotatable relative to the rotating member 1, and a pair of protrusions 32 formed on the outer peripheral portion. , 32 engage with the engaging portions 7, 7 formed on the inner peripheral surface of the recess 6 of the gear 5 to rotate integrally with the gear 5. The shaft hole 8 of the gear 5 is also circular and is rotatable relative to the rotary member 1. The biasing member 9 is formed of an elastic material into a dish shape. The shaft hole 10 of the urging member 9 is formed in the same D shape as the cross-sectional shape of the shaft end portion 3 and has the same size, and is fitted to the shaft end portion 3 so as to be integrally rotatable. Further, the biasing member 9 is fitted to the shaft end portion 3 in a state of being bent toward the friction plates 11, 12 and 13 side, and the caulking portion 33 is formed on the shaft end portion 3. It is locked out. In this way, in the state in which the rotary member side friction plate 11, the gear side friction plate 12, the rotary member side friction plate 13, the gear 5 and the biasing member 9 are fitted to the shaft end portion 3 of the rotary member 1 and prevented from coming off, The movement of each of these members in the rotation axis direction is restricted by the restricting portion 2 of the rotating member 1. Further, due to the elastic force due to the bending of the biasing member 9, the rotating member side friction plate 11, the gear side friction plate 12, the rotating member side friction plate
The gear 13 and the gear 5 are sandwiched between the biasing member 9 and the restriction portion 2 with a predetermined biasing force. Friction plates 11, 12, 13
Is arranged in the recess 6 on the upper side of the gear 5, and the biasing member 9 is arranged in the lower recess of the gear 5.

Now, it is assumed that the gear 5 is the driving side and the gear 5 is rotationally driven via a gear (not shown). The rotation of the gear 5 causes the gear-side friction plate 12 in which the protrusions 32, 32 are engaged with the engaging portions 7, 7 to integrally rotate. The gear side friction plate 12 and the plurality of rotating member side friction plates 11 and 13 are urged by the elastic force of the urging member 9, so that between the gear side friction plate 12 and the plurality of rotating member side friction plates 11 and 13. A frictional force is generated in the rotary member side friction plates 11, 13 by the frictional force, and the rotary member side friction plates 11, 13 and the rotary member 1 are rotationally driven. The rotational force of the rotating member 1 is transmitted to a load (not shown) to drive the load.

The friction transmission mechanism including the gear side friction plate 12 and the rotating member side friction plates 11 and 13 can transmit up to a constant torque, and when a torque larger than that is applied, the gear side friction plate 12 Sliding occurs between the rotating member side friction plates 11 and 13 and functions as a slip mechanism. Therefore, during rotation of the load, an external force is applied to the load side to forcibly stop the rotation of the rotating member 1, or when the drive is stopped, an external force is applied to the load side to force the rotating member 1 to rotate. If it is rotated, the friction transmission mechanism including the gear side friction plate 12 and the rotating member side friction plates 11 and 13 functions as a slip mechanism, and the power transmission mechanism and the drive source connected to the gear 5 are connected. It prevents unreasonable force from being applied to the motor, etc., and protects them.

The rotary member 1 side may be the drive side and the gear 5 side may be the load side. In any case, the drive force is transmitted in the same manner as the above operation, and slip occurs when an overload is applied.

According to the above-described embodiment, the gear side friction plate 12 that engages with the gear 5 and integrally rotates with the gear 5 is provided, and the gear side friction plate 12 is alternately stacked with the plurality of rotating member side friction plates 11 and 13. With this, the slip mechanism is configured, and since it is not necessary to divide the gear into multiple plates as in the conventional case, there is no gap in the gear, and the tooth strength is increased within a predetermined effective thickness of the gear. Since it is possible to secure the same and it is not necessary to align the gears with each other, there is an advantage that the assembly is easy.

Further, since the friction mechanism portion is arranged in the recess 6 of the gear 5 and the friction mechanism portion and the meshing portion of the gear are separated from each other,
There is an advantage that abrasion powder at the meshing portion is unlikely to enter the slip mechanism portion, and even if different lubricant oils are used for the meshing portion and the slip mechanism portion, the oil is not mixed, so that the reliability is improved.

In addition, since the rotational force is received by one gear, the stress is not concentrated on some teeth as in the case where the gear has multiple plates.

Next, an application example of the above embodiment will be described with reference to FIG. In FIG. 3, the slip mechanism according to the above embodiment is arranged between the lower substrate 54 and the upper substrate 55. More specifically, the lower end of the rotating member 1 is rotatably supported by the bearing 57 provided on the lower substrate 54, and the upper substrate 55 is
The main body of the rotary member 1 is rotatably supported by the bearing 56 provided on the.

An AC synchronous motor is used as a drive source on the lower surface of the lower substrate 54.
60 is attached. The AC synchronous motor 60 includes a plurality of magnetic pole pieces 63 formed by cutting and raising a plurality of locations of the lower case 61 along a predetermined circle, and a plurality of magnetic poles formed by cutting and raising a plurality of locations of the upper case 62 along a predetermined circle. It has a piece 64, a single-phase drive coil 66, and a rotor magnet 67. The above pole piece
63 and magnetic pole pieces 64 are alternately arranged so as to draw a cylindrical shape. The drive coil 66 is arranged on the outer peripheral side of the magnetic pole piece 63 and the magnetic pole piece 64 that draw this cylindrical shape via the bobbin 65.
A rotor magnet 67 is arranged on the inner peripheral side of the magnetic pole piece 64. Magnetic poles are formed on the rotor magnet 67 at regular intervals in the circumferential direction. The rotor magnet 67 is rotatably supported by a rotating shaft 68. The upper end of the rotating shaft 68 penetrates the lower substrate 54 and advances to the upper substrate 55,
A pinion 69 is fixed to the upper end of 68. Pinion
The rotational force of 69 is transmitted to the gear 5 constituting the slip mechanism via the reduction gear trains 70, 71, 72, 73.

When AC power is supplied to the drive coil 66 of the AC synchronous motor 60, the magnetic pole pieces 63 and the magnetic pole pieces 64 are alternately magnetized to the N pole and the S pole, and the magnetic poles of the rotor magnet 67 are attracted and repulsed by the magnetism. Rotates in synchronization with the frequency of the AC power supply. This rotational force is transmitted to the gear 5 constituting the slip mechanism via the reduction gear train, and the rotational force of the gear 5 is transmitted to the rotary member 1 via the slip mechanism to drive the load connected to the rotary member 1. To do. Even if an unreasonable external force is applied to the load side, the slip mechanism slips as described above,
Protects the motor 60 and reduction gear train from unreasonable external force.

Next, various modifications of the slip mechanism according to the present invention will be described. It should be noted that the same components as those of the embodiment shown in FIGS. 1 and 2 are designated by the same reference numerals.

The embodiment shown in FIG.
And the rotating member side friction plate 15 are added, and five friction plates 11,12,1
3, 14, 15 are superposed on the upper side of the gear 5 in this order.
Like the other gear side friction plate 12, the gear side friction plate 14 has a circular shaft hole 24 and a pair of protrusions 34, 34 that engage with the engaging portions 7, 7 of the gear 5. The gear 5 is designed to rotate integrally with the gear 5. On the other hand, the rotary member side friction plate 15 has a D-shaped shaft hole 25 that is the same in cross section as the shaft end portion 3 of the rotary member 1, like the other rotary member side friction plates 11 and 13. It is adapted to rotate integrally with the rotating member 1. The other structure is the same as that of the above-mentioned embodiment, and operates in the same manner as the above-mentioned embodiment.

By increasing the number of rotary member side friction plates and the number of gear side friction plates as in the embodiment shown in FIG. 4, it is possible to increase the torque and enhance the reliability of the slip mechanism. There is also an advantage that the slidability can be improved by appropriately selecting the material of each friction plate.

In the embodiment shown in FIG. 5, the rotary member side friction plate 15 and the gear side friction plate 14 added in the embodiment shown in FIG.
It is arranged on the lower side of. Needless to say, the rotary member side friction plate 15 can rotate integrally with the rotary member 1, and the gear side friction plate 14 has its projections 34, 34 engaged with the engaging portions formed on the lower surface side of the gear 5. Rotate with the gear 5. The friction plates 15 and 14 and the biasing member 9 are arranged in a recess formed on the lower side of the gear 3. In the case of this embodiment as well, the same operational effects are obtained as in the embodiment of FIG.

The positional relationship among the rotating member, the rotating member side friction plate, the gear side friction plate, the gear and the biasing member can be arbitrarily exchanged. In the embodiment of FIG. 6, the small-diameter shaft end portion 3 of the rotating member 1 is directed downward, and the biasing member 9, the gear side friction plate 12, the rotating member side friction plate 13, the gear 5, the rotating member side friction plate are attached thereto. 11 is fitted in this order. The gear side friction plate 12 has one protrusion 32.
Although there are only one piece, the one projection 32 engages with the engaging portion 7 of the gear 5 so that the gear side friction plate 12 rotates integrally with the gear 5. Also in the case of this embodiment, a frictional force is generated between the friction plates 12, 13, 11 and the gear 5 by the elastic force of the urging member 9, and the same operational effects are obtained as in the embodiment of FIGS. 1 and 2. .

In the embodiment shown in FIG. 7, the rotary member 1 in the embodiment shown in FIG. 6 is reversed. That is, the small-diameter shaft end portion 3 of the rotating member 1 is directed upward, and the friction plate 11, the gear 5, the friction plate 13, the friction plate 12, and the biasing member 9 are fitted in this order. Also in this case, the same operational effects as those of the embodiment shown in FIGS. 1 and 2 are obtained.

In the embodiment shown in FIG. 8, a pinion 38 is provided integrally with the rotary member 1 in the embodiment shown in FIG. 6, and the pinion 38 is connected to a load. Instead of the pinion 38, a pulley or lever that drives a load may be provided.

The embodiment shown in FIG. 9 corresponds to the embodiment shown in FIG. 4, and has a pair of protrusions 32 and 34 formed on the gear-side friction plates 12 and 14, respectively. Engagement part 7,
It differs from the embodiment of FIG. 4 in that one of the seven is engaged with the protrusion 32 of the gear side friction plate 12 and the other is engaged with the protrusion 34 of the gear side friction plate 14. The function and effect are the same as those of the embodiment shown in FIG.

In the embodiment shown in FIG. 10, a gear-side friction plate 16 and a rotating member-side friction plate 17 are added to the embodiment shown in FIG. Side friction plate
11, gear side friction plates 12, 14, 16, rotating member side friction plates 13, 15,
The gear 5, the rotary member side friction plate 17, and the urging member 9 are fitted in this order. The gear side friction plate 16 has a shaft hole 26 formed in a circular shape, and the pair of protrusions 46, 46 has an engaging portion of the gear 5.
By engaging with 7, 7, it rotates integrally with the gear 5.

As in the embodiment shown in FIG. 10, even if a plurality of gear side friction plates are continuously overlapped, and also a plurality of rotating member side friction plates are continuously overlapped, the gear side friction plates and the rotation are seen from the whole. Since the member-side friction plates are alternately stacked and the gears are stacked thereon, the same operational effects as those of the above-described embodiments can be obtained.

In each of the embodiments described so far, the elastic member formed in the shape of a dish is used as the biasing member, but the biasing member is not limited to this and may have an appropriate shape. For example, in the embodiment shown in FIG. 11, a biasing member 50 having four elastic arms is formed by forming the elastic material into a cross shape. The biasing member 50 has a D-shaped shaft hole 51, and the shaft hole 51 is fitted into the shaft end portion 3 of the rotating member 1 having a D-shaped cross section so as to rotate integrally with the rotating member 1. There is. In this embodiment, the rotary member side friction plate 11, the gear side friction plate 12, the biasing member 50, the gear 5, and the rotary member side friction plate 13 are arranged in this order with respect to the downward shaft end portion 3 of the rotary member 1. It is fitted. Therefore, the urging member 50 is arranged between the gear-side friction plate 12 and the gear 5, but in this case as well, a frictional force acts between the friction plates 11, 12 and 13, and the same action as in the above embodiment is obtained. Produce an effect.

Each friction plate does not necessarily have to be arranged in the recess of the gear, and may be superposed on the flat surface of the gear. The embodiment shown in FIG. 12 is such an embodiment, in which a rotating member side friction plate 13, a gear side friction plate 12, and a rotating member side friction plate 11 are superposed on the flat upper surface of the gear 5. The shaft end 3 of the rotary member 1 penetrates the shaft holes of these members from above. The shaft end 3 has a gear 5
The shaft hole of the biasing member 9 is fitted from below and the caulking portion 33 is formed on the shaft end portion 3 to prevent the above-mentioned members from coming off. The friction plates 11, 12, 13 and the gear 5 are pressed against each other by the urging force of the urging member 9.
A pair of protrusions 75, 75 are formed by bending from the outer peripheral portion of the gear-side friction plate 12, and the protrusions 75, 75 engage with the engaging portions 76, 76 formed on the gear 5 to cause the above friction. The plate 12 is adapted to rotate integrally with the gear 5. In the case of this embodiment as well, the same operational effects as those of the above-mentioned embodiment are obtained.

(Effects of the Invention) According to the present invention, a gear side friction plate that engages with a gear and rotates integrally with the gear is provided, and the gear side friction plate is alternately laminated with a plurality of rotating member side friction plates, thereby slipping. Since the mechanism is configured and there is no need to divide the gear into multiple plates as in the past, there is no gap in the gear and a large tooth strength is ensured within the prescribed effective thickness of the gear. Since there is no need to align the gears with each other, there is an advantage that the assembly is easy.

Further, since the rotational force is received by one gear, the stress is not concentrated on some teeth as in the case where the gear has multiple plates.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of a slip mechanism according to the present invention, FIG. 2 is a sectional front view of the same as above, FIG. 3 is a sectional front view of an application example of the above embodiment, and FIG. 5 is an exploded perspective view showing a second embodiment of the slip mechanism according to the invention, FIG.
FIG. 6 is an exploded perspective view showing a third embodiment of a slip mechanism according to the present invention, FIG. 6 is an exploded perspective view showing a fourth embodiment of a slip mechanism according to the present invention, and FIG. 7 is related to the present invention. FIG. 8 is an exploded perspective view showing a fifth embodiment of the slip mechanism, FIG. 8 is an exploded perspective view showing a sixth embodiment of the slip mechanism according to the present invention, and FIG. 9 is a seventh view of the slip mechanism according to the present invention.
10 is an exploded perspective view showing an eighth embodiment of a slip mechanism according to the present invention, and FIG. 11 is an exploded perspective view showing a ninth embodiment of a slip mechanism according to the present invention. Fig. 12 is a perspective view, a sectional front view showing a tenth embodiment of a slip mechanism according to the present invention, and Fig. 13 is a sectional front view showing an example of a conventional slip mechanism. 1 ... Rotating member, 2 ... Regulator, 5 ... Gear, 7,76 ...
Engaging part, 9,50 urging member, 11,13,15,17 ...... rotating member side friction plate, 12,14,16 ...... gear side friction plate.

Claims (1)

(57) [Scope of utility model registration request] 1. A rotary member, a gear wheel concentrically and relatively rotatably fitted to the outer periphery of the rotary member, and a plurality of rotary member side friction members fitted to the rotary member and rotating integrally with the rotary member. A plate, a gear side friction plate fitted to the rotating member and engaging with an engaging portion formed on the gear to rotate integrally with the gear, a gear fitted to the rotating member, a rotating member side friction The restriction member formed on the rotating member for restricting the movement of the plate and the gear-side friction plate in the rotation axis direction, the gear fitted to the rotating member, the rotating member-side friction plate, and the gear-side friction plate A rotating member side friction plate and a gear side friction plate are alternately stacked. And slip mechanism.