JPH0262459A - Excessive torque detecting device for rotation transmission mechanism - Google Patents

Abstract

PURPOSE:To obviate resetting and enable re-drive after the elimination of a cause for excessive torque occurrence by increasing or decreasing the rotary displacement of a stationary member depending upon transmission torque and independently setting the resilience of an elastic member set belonging to a means for preventing the rotation of the stationary member set. CONSTITUTION:When a limit switch 24 detects excessive torque and is turned from a normally ON state to an OFF state, the operation of a contactor 34 is stopped and the contacts 34A and 34B thereof are turned OFF. Consequently, the operation of a drive motor 30 is interrupted and the transmission of excessive torque is prevented. Concurrently, the self-holding of the contactor 34 is released and even when a switch 24 is reset to an ON state, the motor 30 is not re-started unexpectedly. Then, when transmission torque from a drive shaft 1 to an output shaft 2 is restored to a normal state, a rotation transmission mechanism automatically returns to a normal state. Namely, the reaction torque of an inner gear 11 is also restored to a normal state and the projection 11A of the gear 11 is pushed back to an original position with a plunger 14 or 14A pressed with the projection 11A due to excessive torque. The switch 24 or 24A is thereby reset to an ON state automatically.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention constitutes a part of a rotation transmission mechanism that transmits rotation by meshing with, for example, a planetary gear. The present invention relates to an excessive torque detection device for a rotation transmission mechanism having the following features.

[Conventional technology]

Normally, a rotation transmission mechanism having planetary gears such as a reduction gear detects this excessive torque and stops the drive source to reduce the load. Equipped with an excessive torque detection device to protect the entire device.

The 12th prisoner or the 14th cause is an example of Tokko Koko Sho 52-2837.
This figure shows the configuration of a conventional reduction gear equipped with excessive torque detection equipment disclosed in Publication No. 1i. In Figure 12,
(20 is the drive shaft of the drive motor (not shown), to which the sun gear (2o2) is attached. (203) is the planetary gear meshed with the sun gear (2o2), and the bearing (20 is Connect the side of the output shaft (219,) to the housing (20υ and disc (20B)) through the housing.

Rondo (209) is supported by the spring (21), and the rotational torque transmitted is
9) When the maximum static friction force between the disc (208J and the internal gear wheel (205J) and the housing (20υ) is exceeded.

It rotates around the inner periphery of the bracket (206), and constitutes part of a rotation transmission mechanism that transmits two rotations, and in a normal state acts as a stationary gear.

(213) is formed on a part of the bracket (206) and is press-fitted onto the shaft (212) at the rear opening (21), and is formed on the outer periphery of the internal gear (205) and meshes with the nine tooth surface (21). (215) is an eccentric cam fixed to the protrusion of the shaft (212) with a nut (216), (21υ is a limit switch, and as shown in Fig. 13, the plunger (
218) comes into contact with the maximum diameter of the eccentric cam (215) and is pushed into the limit switch (217), and the limit switch (21υ) is installed in the next state by turning ON between the NO and COM terminals.

Next, the operation of the conventional example shown in FIGS. 12 to 14 will be explained.

Drive motor (from K to drive the motor).

The rotation of the drive shaft (201) is decelerated through a sun gear (202) and a planetary gear (203), and is transmitted to the output shaft (219). At this time, the internal gear (205) receives a reaction torque via the planetary gear (205), but within the range of normal transmitted rotational torque, the disc (208), the internal gear (
2o5) Rotation of the housing is prevented by the static friction force between the housing (20υ). However, if excessive torque is transmitted due to the output shaft (219) side being restrained, etc., the internal gear (
205) rotates when the reaction torque exceeds the maximum value of the static friction force, and the tooth surface (205) on the outer periphery of the internal gear wheel (205) rotates.
The 'fC detection gear (213) rotates.

The eccentric cam (215) also rotates. As a result, a limit switch (21υ plunger (
The eccentric cam (, 215) is separated from 218), and the limit switch (217) is dissipated from the ON state to the OFF state between its NO and COM terminals. 2Using this, the above drive motor (■ not shown) Bring it to a complete stop.

Then, the cause of the excessive torque is removed, and the eccentric cam L215. ) 'fr fixing nut (
216) f Loosen and loosen the eccentric cam (
Push in the limit switch (21υ plunger (218) t) with the long diameter of the limit switch (1
) Reset the NO and OOM terminals of 7 and 1 to the ON state.

[Problem to be solved by the invention]

Since the excessive torque detection device of the conventional rotation transmission mechanism is configured as described above, after excessive torque is applied and the excessive torque detection device is activated, before restarting operation,
Another problem is that it is necessary to reset the eccentric cam position limit switch to return it to its original position, which indicates normal operation, and the work required to reset it is quite cumbersome.

This invention has been made to solve the above-mentioned problems, and there is no need to operate to reset the excessive torque detection device, and once the cause of excessive load torque is removed, it can be used as is. Rotary Den that can be driven again: i! The purpose of this invention is to obtain an excessive torque detection device for a mechanism.

[Means to solve the problem]

The excessive torque detection device for a rotation transmission mechanism according to the present invention constitutes a part of a rotation transmission mechanism that fully transmits two rotations, fully supports the two rotation transmission member, or engages with the rotation transmission member, and is configured to operate within a predetermined range. a stationary member that is rotatable at the stationary member; a stationary member rotating assembly means having an elastic member that engages with the stationary member and suppresses rotational displacement of the stationary member to an amount corresponding to the amount of torque transmission; It is provided with excessive torque detection means for detecting that the amount of rotational displacement of the member has reached a predetermined amount.

However, in the excessive torque detection device for a rotation transmission mechanism according to the first invention, the excessive torque detection device for a rotation transmission mechanism according to the second invention is configured such that the excessive torque detection device for a rotation transmission mechanism according to the first invention A pair of member rotation prevention means and a pair of excessive torque detection means are provided, and the elastic forces of the elastic members of the pair of stationary member rotation prevention means are independently provided.

[Effect]

Torque is transmitted to the rotation transmission mechanism in this starting BAK via a two-rotation transmission member, and the stationary member receives a reaction when the torque is transmitted, and rotates according to the amount of torque transmitted within the elastic deformable range of the elastic member. death.

The excessive torque detection device fl is activated when the amount of rotational displacement of the stationary member reaches a predetermined amount, and detects transmission of excessive torque.

Further, in the pair of stationary member rotation prevention means in the second invention, the elastic coefficients of the elastic members are independently set for each of the forward and reverse rotation directions of the stationary member. Transmission of a predetermined excessive torque is detected for each direction of reverse rotation.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 9. Fig. 1 is a side sectional view of a speed reducer as an example of a rotation transmission mechanism, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. 3 constitutes a part of an excessive torque detection device of the rotation transmission mechanism. A cross-sectional view of the excess torque detection means, FIG. 4 is an exploded perspective view showing the components of the excess torque detection means shown in 3-.
below.

An excessive torque detection device for a reduction gear will be explained.

First, the overall structure of a speed reducer according to an embodiment of the present invention will be explained with reference to FIGS. 8g1 and 2. In Fig. 1, C1) is the drive shaft of the next drive motor (2) shown in Fig. 9, and (2) is the shaft connected between the bracket az and the third housing side via the pole bearings (5h), (5B). This is a supported transmission shaft, and the first gear (2k) fixed to this transmission shaft (2) meshes with the tooth surface (1A) formed on the outer periphery of the shaft end of the drive shaft (1). There is.

(4) is a spur gear with two concentric outer surfaces formed, the first gear (4A) meshes with the N2 gear (2B) of the transmission shaft (2), and the first gear (4A) meshes with the N2 gear (2B) of the transmission shaft (2). ) meshes with the planetary gear (5) as a sun gear. This planetary gear +
51 is rotatably supported by a pin shaft in the first housing (8) via an oil-impregnated metal (9), and is connected to an internal gear wheel (described later).
It meshes with. (7) is the output shaft, which is an oil-impregnated metal (
6), and is disposed concentrically with the spur gear (4) through a spline portion (8A)K, and is integrally connected to the first housing (8) through a spline portion (8A)K. In addition, the above transmission shaft (2), spur gear (
4).

The planetary gear (5), the first housing (8), and the output shaft (7) constitute the main part of the rotation transmission member.

αυ is a planetary gear (5
A pair of protrusions (1)AJ, (,1)B) are formed axially symmetrically on the internal gear wheel as a stationary member that meshes with the inner toothed wheel. α2 is a bracket), Q3 is a second housing, and at the abutting part of this second housing a3 and the bracket α2, a recessed part (1
2A)K The internal gear wheel aυ is rotatably arranged with a predetermined gap. In addition, the above bracket α2
There is a groove (12B) as shown in the second prisoner.

(12 ridges are formed, and the protrusion (1) of the internal gear αυ
A) (1) B) are configured to be able to rotate within the range of this groove (12B), (12 (J). Also, the third housing The output shaft (7) is firmly supported by a ball bearing (L9) and is prevented from moving in the p-axis direction by a washer (2) and a self-lock nut (Q1).

In addition, c! 3 is a plate A, C20) is a plate B, and (2) is a screw, which constitute a pair of excess torque detection means.

The details are shown in FIG. 4 and will be described later.

The second factor is the A-A sectional view in FIG. 1, which shows the relationship between the internal gear αυ as a stationary member and a pair of stationary member rotation prevention means that prevent rotation of this stationary member. In figure 1,
Q41. (14A) is a plunger, +15° (15
A) is a coil spring as an elastic member, (161, (1
6AJ is an adjustment nut, and the pair of stationary member rotation prevention means is the plunger a4. Coil spring N5. Adjustment nut αe, plano jaw (14A), coil spring (15
Consists of A8 adjustment nuts (16A), bracket) (
A pair of mounting holes (12D) formed in 12 are attached to both sides of the protrusion (1)A) so as to prevent the rotation of the internal toothed wheel a1 (attached to 12).
It is held by the head of 14AJ. Then, by turning the adjusting nut (Lll, (16A)), the inner audience wheel (Il)
The rotation prevention force for l is adjusted.

Internal gear wheel (Iυ protrusion (1) A), (1) BJ is line 1
As shown in the figure, the tips are formed in an L-shape, and the tips of the protrusions (1)A) and (1)B) are as shown in the third factor.

The limit switch 041i, which constitutes a part of the excess torque detection means, is used as an actuation piece for turning ON and OFF.

A pair of excess torque detection means for detecting that the amount of rotational displacement of the stationary member has reached a predetermined amount is as shown in FIG.
The limit switch @ and the switch actuator @ are attached to plate A @ via a spacer with screws (to), and a lock wire is hung around this screw (1) to prevent rotation. Switch actuator (25A
, l and limit switch (24A) 'i Installed with a screw (26A) using a washer @, and this screw (26A) was prevented from rotating in the same way as the screw (to) 7. c.
The above-mentioned plate A■ and plate B@ are attached to the second housing (
13 and is fixed to the bracket (2) with four screws as shown in the first frame. In the circuit diagram of the ninth embodiment, ■ is shown in FIGS. 1 to 9. The operation of this embodiment will be explained below. When the drive motor 3G shown in FIG. 8 is activated, the drive shaft (1) shown in FIG. 1 rotates.

The rotation is caused by the first and second gears (2k
).

(2B), the first gear (4A) of the spur gear body (4), the second gear (4B, 1) as a large descending gear, the planetary gear (5
), a first housing (8) that rotates as the planetary gear (5) revolves, and is connected to the first housing (8) through a spline portion (8A) and is transmitted to the next output shaft (7). Ru. The internal gear αB receives reaction torque through the planetary gear (51 gold) that meshes with it, and tries to rotate in the opposite direction to the revolution direction of the planetary gear (5), but the protrusion of the internal gear αυ In part (1) A), the coil in contact with this is energized by (15A) and the friend flanger 1
41. (14A) prevents rotation. Strictly speaking,
Depending on the size of the reaction torque mentioned above, the coil will not fit 9 or (
15A) is compressed and deformed, and the internal gear αυ corresponding to this deformation rotates, and the amount of rotational displacement increases or decreases approximately in proportion to the magnitude of the transmission torque of this rotation transmission mechanism.

As shown in Fig. 5, the direction of rotation due to the reaction torque of the inner wheel 1) 1) is counterclockwise, and the amount of rotational displacement of the inner wheel allO, which is displaced by the coil spring a9, is transmitted. When the torque reaches a level equal to the predetermined excessive torque, as shown in Fig. 6, the limit switch is activated and the protrusion (1) A) of the inner wheel (1) 1 is activated.
The plunger is pushed in and operated via the switch actuator (c), that is, the connection between the No and cOM terminals of the limit switch I24 is released from the normally ON state to the OFF state.

The 9th prisoner is filled coil 01), l, 3 according to rotation direction.
1A) and whose rotation direction is selected by a changeover switch (to). (34A) and (54B) are turned ON.

The drive motor is connected to the power field and operated,
The contactor I is self-retaining.

However, the above limit switch @ is inserted into the above contactor example in series with the other limit switch (, 2AJ), and when the limit switch @ detects excessive torque and changes from the normally ON state to the OFF state, the contactor The operation of the example is stopped and the contacts of this contactor example (34A), (34
When B) becomes 0IFF, the operation of the drive motor is stopped and the transmission of the excessive torque is prevented. At the same time, the contactor is also self-retaining, and even if the limit switch returns to its original ON state, the drive motor will not be restarted inadvertently.

If the rotation direction of the internal gear αυ due to the driving torque is clockwise as shown in Fig. 7, the operation will be opposite to the above case, and the limit switch (24 The gear wheel ano protrusion (1) B) is operated by pushing its plunger through the Nyop switch actuator (25A) i, that is, the N of the limit switch (24A)
The connection between the o and OOM terminals is constantly switched from ON to OFF.

Then, in the same way as when the limit switch @ is operated, the ninth
In this case, the operation of the drive motor is stopped, and the transmission of the excessive torque is prevented.

When the transmission torque from the drive shaft (1) to the output shaft (2) returns to normal, the rotation transmission mechanism automatically returns to its normal state.

In other words, the reaction torque of the inner and outer wheels aVO has also returned to its normal state, and the projection t of the P3 gear αD, 1) A) is the plunger that was pushed into this projection (1) A) when excessive torque was applied. It is pushed back to its original state by a4 or L14AJ, and at this time the 7t IJ Mitswitch (to) or (
24AJ always automatically recovers to the 01J state from OFF'FF. Therefore, eliminate the cause of excessive torque being transmitted, and then turn on the start pushbutton switch again as shown in the 9th cause.
To do so, Xiaomi resumes driving.

When restarting the operation of the drive motor (2), there is no need for operations such as readjusting the eccentric cam in the conventional example.

In the above embodiment, if it is desired to separately select the upper limit of the transmitted torque to be detected as excessive torque in the forward and reverse directions, select a coil spring a5° (15A) with an elastic modulus suitable for each, adjustment) (is
, (Achieved by adjusting the screwing amount of 16AJ, and if the difference in the upper limit value of the transmission torque is small, the adjustment nut αa.

(16k) is adjusted only by the screwing amount.

In addition, although the above embodiment uses a support method that provides a holding torque for rotation in both forward and reverse directions, if nine rotations are limited to only one direction, the stationary member rotation prevention means and the excess torque detection means may be used. It is sufficient to have one set of each.

In addition, in the above example, the spring fi5° (1
5A), we have shown a comparative example using a coil spring, but it would be better if the amount of movement of the plunger (14, (14A) can be adjusted by elastic force.2) Even if it is a countersunk spring, the same effect can be obtained. There is.

The 10th port and the 1st) 1i4 are another embodiment of the present invention, and show a cross section of a reducer and its excessive torque detection means as an example of a one-rotation transmission mechanism, and FIG. 10 is a front sectional view; gIf indicates a side cross section.

In the figure, (10) is a driving shaft connected to an electric motor (not shown), (102,) is a drive shaft (10) is a sun gear connected to the shaft end, (103) is a sun gear. (
(102) meshes with the planetary gear; (105) is an output shaft, and the planetary gear (i03) is pivotally supported by a revolution shaft disposed at the end of this shaft. The above sun gear (102)
.

Play MI! 1) One wheel (103), a revolution axis (10 wheels), and an output shaft (105) constitute the main S of the two-rotation transmission member.

L106) is an internal gear wheel as a stationary member, which is meshed with the planetary gear (105), has a protrusion (106A)'i, and has a bearing (106A) on its outer periphery.
7) is rotatably held in the housing (109J). (1) is the plunger, αD is the coil spring as an elastic member, (1) and 2) are the coil spring ridges.
The pair of stationary member rotation prevention means are inserted into a pair of cylindrical parts formed in the housing (109,) and each of the pair of cylindrical parts. The above-mentioned plunger (1) is arranged, and the coil spring (1)
The coil spring (106) is composed of spring pressure adjustment screws (1) and 2), and is configured to prevent the internal gear wheel (106) from rotating.
1) The head of the friend bra/jar (1)0) is energized by 1) and swings to contact and press both ends of the chiaki projection (106A). (1) RI is a limit switch fixed to the housing 1, 109), (1) 3J is an internal gear pulley (1
This is a stroke adjustment screw that adjusts the stroke of the limit switch so that it operates at a predetermined amount of rotational displacement of the housing (109).
It is adjusted externally using a screwdriver. (1
) 5) is a screw that is covered to prevent dust from entering except when adjusting the stroke adjusting screw (1) 3J.

Next, the operation of the embodiment shown in Figure 10 and Figure 1) will be explained. Drive shaft (10 rotations.

Sun gear (102), planetary gear (103), revolution axis (
104) and is transmitted to the output shaft (105J).

At this time, the internal gear wheel (10) tries to rotate due to the reaction torque, but the protrusion (106A) of the internal gear wheel (106) prevents the rotation. The coil is held by a plunger (1) which is biased by a spring (1), and can only rotate within the range of elastic deformation of the coil. The amount of rotational displacement increases or decreases approximately in proportion to the magnitude of the transmitted torque, for example, based on the output shaft (105) t', and when steady torque is transmitted, the amount of rotational displacement is very small. , torque is normally transmitted from the drive shaft (10j) to the output shaft (105). However, if an excessive torque exceeding the limit value is transmitted, depending on the magnitude of this transmitted torque, the inner garden wheel (the 9-stroke p-shaped protrusion (IQ6k) with a large rotational displacement) is The limit switch (
1) When the plunger is pushed in and operated, the connection between the ON limit switch (1) 4) and the COM terminal is released from constantly ON to OFF, so excessive torque transmission can be detected from the change in this contact. to completely stop the drive motor (not shown).

In this embodiment, as in the embodiments previously explained in FIGS. 1 to 9, when transmission of excessive torque is detected and the drive motor (not shown) is stopped, the one-rotation transmission mechanism is activated. Since the motor is automatically restored to a state in which operation can be resumed, the operation can be resumed by removing the cause of the excessive torque and restarting the drive motor.

The limit torque is set by adjusting the screwing amount of the spring pressure adjusting screws (1) and 2) in each direction of rotation.

To adjust the limit switch (1) for installation errors, remove screw (1) 5, l'i from the housing (109), and use a screwdriver (not shown) to screw (1) 3).
Do this by rotating.

In addition, in the above embodiment, the spring (1) is a coil spring, and the plunger (1) may be of any type as long as its movement amount can be adjusted by elastic force2.For example, it may be a disc spring or a torsion spring. A similar effect can be obtained.

Further, although a negative speed reduction mechanism is shown, a multi-stage speed reduction mechanism may be used.

Furthermore, in the above @1 and second embodiments, the main part of the two-rotation transmission member is made up of a planetary gear, and the main part of the stationary member is made up of an internal gear. A housing that is directly connected to a shaft, supports a planetary gear, and can be rotated next time is used as a stationary member, and its rotation, that is, the revolution of the planetary gear, is limited to a predetermined amount by a stationary member rotation prevention means. Even if it is a rotation transmission mechanism of a type in which rotation is transmitted to the output shaft via a sun gear, the planetary gear that meshes with the sun gear and rotates, and the internal gears that rotate and mesh with the planetary gear. By providing the following excessive torque detection bag fIK as shown in the first and second embodiments, the transmission of excessive torque of the rotation transmission mechanism can be detected. A similar effect can be obtained.

〔Effect of the invention〕

As described above, according to the invention of Ml, the amount of rotational displacement of the stationary member that partially and completely constitutes the two-rotation transmission mechanism is increased or decreased in accordance with the increase or decrease of the total transmission torque, so that the amount of rotational displacement is This can be used to operate the excess torque detection means to detect excessive torque that exceeds the limit value, and when the transmitted torque returns to normal, the excess torque detection means is automatically reset without the need for manual resetting. This has the effect of allowing operation to be resumed without requiring any additional effort.

Further, according to the second invention, each pair of stationary member rotation prevention means and excess torque detection means are provided, and the elastic force of the elastic member included in the pair of stationary member rotation prevention means can be independently set. Therefore, there is an effect that the limit value of the transmitted torque can be set separately for the forward and reverse rotation directions.

[Brief explanation of the drawing]

Figures 1 to 9 are diagrams showing a first embodiment common to the first and second inventions. 2 is a sectional view taken along the arrow A-A of the first prisoner; FIG. 3 is a sectional view of the excessive torque detection means that constitutes a part of the excessive torque detection device; Figure fJ4 is the component parts of the excessive torque detection means. FIGS. 5 and 7 are explanatory diagrams of the operation of the stationary member rotating means that prevents rotation of the internal gear as a stationary member, and FIGS. 6 and 8 are diagrams showing the above-mentioned excessive torque detection. FIG. 9, an explanatory diagram of the operation of means O, is a circuit in which a limit switch constituting a part of the excess torque detection means is inserted between the drive motor of the reduction gear and the power source. Figure 10 and Figure 1) are from this first
FIG. 10 is a front sectional view of a rotation transmission mechanism equipped with an excessive torque detection bag*, and 1) is a diagram showing a second embodiment common to the second invention. It is a BB sectional view. Figure 12 shows the side cross section of the conventional device, the first factor, and Figure 1j explains the operation of the limit switch of the conventional device.
It is. In Figures 1 to 9, (1) is the drive shaft, (2) is the transmission link shaft, (4) is the spur gear, (5) is the planetary gear, (71 is the output shaft. (8) is the first ° Housing, an is internal gear wheel,
(1) A) is the internal gear protrusion, α3 is the bracket, α3 is the second housing, α4, (14A) is the plunger, (15A) is the coil spring, α19, L16
AJ is the adjustment nut, αS is the third housing, H, (
24A) is a limit switch. The field indicates the drive motor. (10) is the drive shaft. (102) is the sun gear, (103) is the planetary gear, (
105) is the output shaft, (106) is the internal gear wheel, (1
06AJ is the protrusion of the internal gear, (109) is the housing, (1) 0) is the plunger, (1) is the coil spring, (1) 2) is the spring pressure adjustment screw, (1) 3) ,
(1) 3A) is a stroke adjustment screw, (1) (1) 4
A] indicates a limit switch. Note that in the two figures, the same reference numerals indicate the same or equivalent parts.

Claims (2)

[Claims] (1) constitutes a part of a rotation transmission mechanism that transmits rotation, supports a rotation transmission member, or engages with a rotation transmission member;
a stationary member that is rotatable within a predetermined range; and a stationary member rotation preventing means that includes an elastic member that engages with the stationary member and suppresses rotation of the stationary member to an amount of rotational displacement that corresponds to the amount of torque transmission. An excessive torque detection device for a rotation transmission mechanism, comprising an excess torque detection means for detecting when the amount of rotational displacement of the stationary member reaches a predetermined amount. (2) A pair of stationary member rotation prevention means and an excessive torque detection means are provided in correspondence with forward and reverse rotation of the rotation transmission mechanism, and the elastic force of the elastic member of the pair of stationary member rotation prevention means is adjusted respectively. An excessive torque detection device for a rotation transmission mechanism according to claim 1, characterized in that the device is set independently.