JPH0623680B2 - Slip detector for torque transmission mechanism - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slip detecting device for detecting a slip on a power transmission surface in a rotational force transmission mechanism for transmitting a rotational force of a drive shaft to a driven shaft.

[0002]

2. Description of the Related Art FIG. 5 is a schematic diagram showing the outline of a conventional slip detecting device for an electromagnetic clutch.

Reference numeral 1 is a motor for rotating the drive shaft 2, 3 is an electromagnetic clutch for transmitting the rotational force of the drive shaft 2 to the driven shaft 4, 5
Is a drive-side tachometer, 6 is a driven tachometer, and 7 is a control / monitoring unit.

A motor 1 rotates a drive shaft 2 at a constant speed, and a drive side tachometer 5 is provided at one end of the drive shaft 2.
Is provided, and the electromagnetic clutch 3 is connected to the other end. When the electromagnetic clutch 3 internally presses the opposing clutch plates (not shown) by an electromagnetic force, the clutch plate having the power transmission surface transmits the rotational force of the drive shaft 2 to the driven shaft 4. The driven shaft 4 is provided with a roller (not shown), a rotary tool, and the like, which are not shown, and a driven-side tachometer 6 is provided at the end.

The drive-side tachometer 5 and the driven-side tachometer 6 output rotation speed signals R1 and R2 corresponding to the rotation speeds of the drive shaft 2 and the driven shaft 4, respectively, to the control / monitor section 7. The control / monitor 7 calculates the rotation speed of the drive shaft 2 and the rotation speed of the driven shaft 4 by processing the rotation speed signals R1 and R2. Here, if an excessive rotational load is generated on the driven shaft 4, a force exceeding the allowable transmission force may be applied to the electromagnetic clutch 3 and the electromagnetic clutch 3 may be broken to prevent the rotational force from being transmitted. In such a case, the control / monitoring unit 7
It detects that a speed difference has occurred between the rotational speed of the drive shaft 2 and the rotational speed of the driven shaft 4, and outputs an alarm signal to an alarm panel or the like.

FIG. 6 is an explanatory view of a conventional slip detecting method in a shaft coupling, and the members corresponding to the members described with reference to FIG.

The shaft joint 8 is connected to the drive shaft 2 and the driven shaft 4 and transmits the rotational force of the drive shaft 2 to the driven shaft 4. The shaft joint 8 is configured so that the contact force of the contact surface (not shown) with respect to the outer peripheral surface of the drive shaft 4 can be adjusted by the action of hydraulic pressure or the like. Axis 4
The contact surface, which is a power transmission surface, slips with respect to the outer peripheral surface of the shaft and protects the mechanism on the drive shaft 2 side.

An overload on the driven shaft 4 is often caused by an abnormality of a device or the like connected to the driven shaft 4, and it is important to detect the occurrence of the overload at an early stage for maintenance. As a method therefor, for example, as shown in FIG. 6, the alignment marks 4a and 8a are formed on the outer peripheral surface of the driven shaft 4 and the outer peripheral surface of the shaft coupling 8 by engraving or coating. The maintenance staff records in advance the relative position of the match mark 4a with respect to the match mark 8a,
By periodically checking the positions of the matching marks 4a and 8a, it can be found that the contact surface of the shaft coupling 8 slips with respect to the outer peripheral surface of the driven shaft 4.

[0009]

However, it is difficult for the slip detecting device described with reference to FIG. 5 to detect the slip between the clutch plates that occurs in the electromagnetic clutch 3 in a short time. In many cases, it is not possible to detect abnormalities in the device, etc. until the item is completely damaged.

Further, in the slip detecting method described with reference to FIG. 6, since it is necessary to visually check the matching marks 4a and 8a, for example, an operator or the like at a remote place cannot find the slip, and It takes a certain time from the occurrence of slip to the discovery of slip.

In order to solve the above problems, an object of the present invention is to detect the occurrence of slip on the power transmission surface with high accuracy and to notify the occurrence of slip to a remote place almost at the same time as the occurrence of slip. To provide a slip detecting device.

[0012]

In order to solve the above problems, the present invention relates to a rotational force which is connected to a drive shaft and a driven shaft to transmit the rotational force of the drive shaft to the driven shaft via a power transmission surface. A slip detecting device for detecting a slip on the power transmission surface of a transmission mechanism, comprising a drive-side detected portion provided on a drive-side rotation surface with respect to the power transmission surface and a driven-side rotation surface with respect to the power transmission surface. A driven side detected portion provided on the drive side sensor, a drive side sensor that detects the drive side detected portion at an opposed position, a driven side sensor that detects the driven side detected portion at an opposed position, and a drive side sensor A signal processing circuit for detecting a time delay of the detection timing of the driven side sensor with respect to the detection timing. Further, the driving side sensor and the driven side sensor are constituted by proximity switches. Further, it is characterized in that the rotational phase of the driven side detected portion is displaced from the driving side detected portion by a predetermined amount in the initial state.

[0013]

According to the above means, the drive side sensor for detecting the drive side detected portion of the drive side rotation surface at the facing position and the driven side sensor for detecting the driven side detected portion of the driven side rotation surface at the facing position. And a signal processing circuit for detecting a time delay of the detection timing of the driven side sensor with respect to the detection timing of the driving side sensor, the rotation of the driven shaft to which the rotation force is transmitted via the power transmission surface with respect to the drive shaft. The position change in the moving direction can be detected. Further, since the drive side sensor and the driven side sensor are composed of proximity switches, it is possible to detect the drive side detected portion or the driven side detected portion at the facing position and output an electrical detection signal to the outside. . Further, by shifting the rotational phase of the driven side detected portion with respect to the driving side detected portion, it is possible to delay the detection timing of the driven side sensor by a predetermined time with respect to the detection timing of the driving side sensor in the initial state. it can.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a slip detecting device for a shaft coupling according to an embodiment of the present invention, and FIG. 2 is a side view showing a part of the shaft coupling and the proximity switch shown in FIG. 1 as a sectional view. It is a figure.

The structure of the shaft coupling 20 will be described with reference to FIGS. 1 and 2.

Reference numeral 12 is a drive shaft which is connected to a motor (not shown) or the like to transmit the rotational force, and 14 is a driven shaft which transmits the rotational force of the drive shaft 12 via a shaft coupling 20.

The shaft coupling 20, which is a rotational force transmitting mechanism, is composed of a drive shaft fixing portion 30 and a driven shaft fixing portion 40, and the drive shaft fixing portion 30 and the driven shaft fixing portion 40 have respective flanges 31, 41.
Are connected by a bolt 21 and a nut 22 to be integrated.

An insertion hole 32 is formed in the drive shaft fixing portion 30,
A key groove 32a that is long in the axial direction is formed on the inner surface of the insertion hole 32. The drive shaft 1 having the key 12a fitted in the insertion hole 32.
The drive shaft 12 is securely fixed to the drive shaft fixing portion 30 by inserting 2 and fitting the key 12a into the key groove 32a.

The driven shaft fixing portion 40 is integrally formed with a fixing portion main body 42 having an insertion hole 42a formed therein, a tubular sleeve 43 inserted into the insertion hole 42a, and an outer peripheral surface of the fixing portion main body 42. The shear tube 44 covers a part of the surface. The sleeve 43 has an axially long keyway 43 on the inner surface.
a is formed, the driven shaft 14 with the key 14a fitted therein is inserted into the sleeve 43, and the key 14a is fitted into the key groove 43a, whereby the driven shaft 14 is securely fixed to the sleeve 43. ing.

The fixed portion main body 42 is provided with a hydraulic chamber 42 in the inner circumferential direction.
b is formed and the hydraulic chamber 42b communicates with the hydraulic chamber 42b in the radial direction.
By forming c and sealing the hydraulic passage 42c with the sealing member 45, the hydraulic chamber 42b is in a sealed state. The sealing member 45 is internally formed with a hole communicating with the hydraulic passage 42c up to the vicinity of the end, and is attached with the shearing portion 45a protruding from the outer peripheral surface of the fixed portion main body 42. Shear part 45a
Since the notch is formed, it is easily sheared by the shearing force in the circumferential direction.

Further, the inner peripheral surface of the insertion hole 42a and the sleeve 43
The outer peripheral surfaces of are configured as power transmission surfaces 42d and 43d,
The drive shaft 12 and the rotational force are transmitted to the driven shaft 14 via the power transmission surfaces 42d and 43d. At the time of power transmission, high-pressure hydraulic oil is injected into the hydraulic chamber 42b of the fixed part main body 42, and the partition between the power transmission surface 42d and the hydraulic chamber 42b bulges in the axial center direction due to the pressure of the hydraulic oil. The power transmission surface 42d of the main body 42 and the power transmission surface 43d of the sleeve 43 are fixed by frictional force. Here, the partition wall is elastically deformed, and the hydraulic chamber 42
By removing the hydraulic pressure of b, the power transmission surface 42d does not exert a frictional force on the power transmission surface 43d of the sleeve 43, so that the transmission of the rotational force to the driven shaft 14 is stopped.
Further, in the fixed portion main body 42, bearings 42e are arranged in the vicinity of both ends of the power transmission surface 42d, and the bearing 42e is the power transmission surface 4 of the sleeve 43 in a state where the rotational power is not transmitted.
The sleeve 43 is brought into contact with 3d so that the sleeve 43 can be smoothly rotated.

The driven shaft 14 is, for example, a rolling roll (not shown).
And transmits the rotational force for rolling the steel material. However, if the load at the time of rotation of the driven shaft 14 increases due to a trouble of the rolling mill or the like and becomes overloaded, a force greater than the friction force is generated between the power transmission surface 42d and the power transmission surface 43d. Causes slip. When the slip occurs, the shear tube 44 integrated with the sleeve 43 rotates relatively to the fixed portion main body 42, and thus shears the shearing portion 45a of the sealing member 45 when the slip amount exceeds a predetermined amount. . The shearing of the shearing portion 45a causes the high-pressure hydraulic oil in the hydraulic chamber 42b to flow out from the hole of the sealing member 45. At this time, since the sleeve 43 and the driven shaft 14 are in a state of being able to rotate smoothly with respect to the fixed portion main body 42, the rotational force of the drive shaft 12 is not transmitted by the shaft coupling 20. Therefore, the driven shaft 14
The rotation of the shaft coupling 20 is stopped by the load of the connected rolls, and the shaft coupling 20 is rotated by the drive shaft 12 with a low load only on the member arranged on the drive shaft 12 side with respect to the power transmission surface 42d.

Detecting a slip between the power transmission surfaces 42d and 43d is effective for detecting the occurrence of overload at an early stage, and stopping the driven shaft 14 due to overload is a serious problem in operation. Since it is a serious trouble, it is required to contact the operator early by an alarm or the like.

As shown in FIG. 1, in the shaft coupling 20, the proximity switches 62a and 62b, which will be described later, are provided on the outer peripheral surface of the drive shaft fixing portion 30 and the outer peripheral surface of the shear tube 44, which are rotating surfaces.
The strikers 61a and 61b, which are the detected parts of the, are fixed. The strikers 61a and 61b are formed of iron or the like, which is a magnetic material, are in a state of protruding with respect to the outer peripheral surface, and are fixed so as to have a certain amount of phase difference at the initial position.

Proximity switches 62a and 62b are arranged on the outer peripheral surface of the drive shaft fixing portion 30 and the outer peripheral surface of the shear tube 44 so as to face each other. The proximity switch 62a detects that the striker 61a is at the facing position. The proximity switch 62b detects that the striker 61b is in the facing position.

The detection signals of the proximity switches 62a and 62b are output to the signal processing circuit 50, and the signal processing circuit 50 detects the slip on the power transmission surfaces 42d and 43d by the detection signal and outputs an alarm signal to the alarm circuit 60. .

FIG. 3 is a circuit diagram showing the outline of the signal processing circuit, and FIG. 4 is a timing chart showing an example of the detection signal output from the proximity switch.

The signal processing circuit 50 includes flip-flops 51,
It is composed of an AND gate 52, a counter 53, a timer 54 and the like. The proximity switches 62a, 62b are the strikers 61a, 6
When it detects 1b, it outputs a rectangular pulse signal. The drive side detection signal of the proximity switch 62a is input to the set input terminal S of the flip-flop 51 and the AND gate 52, and the driven side detection signal of the proximity switch 62b is input to the reset terminal R of the flip-flop 51. The flip-flop 51 outputs an alarm detection signal to the AND gate 52 and the timer 54 at the timing when the driving side detection signal is input, resets the alarm detection signal at the timing when the driven side detection signal is input, and resets the counter 53. The reset signal is output to the terminal R.

When a slip occurs on the power transmission surfaces 42d and 43d of the shaft coupling, the phase difference between the striker 61a and the striker 61b becomes larger than the initial setting, so that the reset timing of the alarm detection signal is delayed, resulting in alarm detection. The output time t of the working signal becomes longer than the initial value. Further, when the shearing portion 45a is sheared by the shear tube 44 and the rotational force is not transmitted to the driven shaft 14, the rotation of the shear tube 44 stops, the alarm detection signal is not reset, and the flip-flop 51 continues. Is output from.

The signal processing circuit 50 uses two methods for the shaft coupling 20.
To detect anomalies in.

The timer 54 has a time-up time t0 set in advance in an internal memory (not shown), counts the output time t of the alarm detection signal, and issues an alarm when the output time t matches the time-up time t0. It outputs a time-up signal to the circuit 60. As described above, the power transmission surface 42
When a slip occurs in d and 43d, the output time t of the alarm detection signal increases corresponding to the slip amount. Therefore, if the time-up time t0 is set appropriately, the time-up signal is generated at the timing when the desired amount of slip occurs. Can be output to the timer 54.

The counter 53 is an internal memory (not shown).
The count-up value k0 is set in advance in the
When the shaft coupling 20 stops transmitting torque to 14,
Since the driven side detection signal is not output, the reset signal is not output from the flip-flop 51 to the counter 53. Therefore, the counter 53 continuously counts the number of times the drive side detection signal is input, and as shown in FIG.
The count value c of is increased. Further, the counter 53 outputs a count-up signal to the alarm circuit 60 at the timing when the count value c matches the count-up value k0.
Here, for example, when "2" is set as the count-up value k0, the counter 53 can output the count-up signal at the timing when the shaft coupling 20 makes one rotation idle without transmitting the rotational force to the driven shaft 14. .

As described above, the strikers 61a, 61b,
According to the slip detection device of the shaft coupling 20 configured by the proximity switches 62a and 62b, the signal processing circuit 50, and the like, a minute slip on the power transmission surfaces 42d and 43d is detected by appropriately setting the time-up time t0. Is possible,
It is possible to detect an abnormality in the device connected to the driven shaft 14 at an early stage.
Further, the slip of the power transmission surfaces 42d, 43d or the suspension of the transmission of the rotational force to the driven shaft 14 is output to the alarm circuit 60 as a time-up signal or a count-up signal which is an electrical signal. It is possible to centrally monitor a large number of shaft couplings 20 and to notify an operator or the like of the occurrence of slip on the power transmission surfaces 42d and 43d and the suspension of the rotational force transmission in the shaft couplings 20 due to overload at substantially the same time as the generation.

[0035]

As described above, according to the present invention, the driving side sensor for detecting the driving side detected portion of the driving side rotating surface at the facing position and the driven side detected portion of the driven side rotating surface for the facing position. Drive of the driven shaft to which the rotational force is transmitted via the power transmission surface by the driven side sensor which is detected by and the signal processing circuit which detects the delay of the detection timing of the driven side sensor with respect to the detection timing of the driving side sensor. Since it is possible to detect a positional change in the rotational direction with respect to the shaft, it is possible to detect with high accuracy that slip has occurred on the power transmission surface.Furthermore, the drive side sensor and the input side sensor are configured by proximity switches. , It is possible to detect the drive-side detected part or the driven-side detected part at the facing position and output an electrical detection signal to the outside. An abnormal signal can be output to the road, etc. almost at the same time as the slip on the power transmission surface, and the rotational phase of the driven side detected part is shifted with respect to the drive side detected part. In, since the detection timing of the driven side sensor can be delayed by a predetermined time with respect to the detection timing of the driving side sensor, for example, the detection signal of the driven side sensor can be used as a reset signal of the abnormality detection signal in the signal processing circuit. .

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an outline of a slip detecting device for a shaft coupling, which is an embodiment of the present invention.

FIG. 2 is a side view showing a part of the shaft coupling and the proximity switch shown in FIG. 1 as a sectional view.

FIG. 3 is a circuit diagram showing an outline of a signal processing circuit of this embodiment.

FIG. 4 is a timing chart showing an example of a detection signal output from the proximity switch of the present embodiment.

FIG. 5 is a configuration diagram showing an outline of a conventional slip detection device in an electromagnetic clutch.

FIG. 6 is an explanatory diagram of a conventional slip detection method for a shaft coupling.

[Explanation of symbols]

12 ... Drive shaft, 14 ... Drive shaft, 20 ... Shaft coupling, 30 ... Drive shaft fixing part, 40 ... Drive shaft fixing part, 50 ... Signal processing circuit,
61a, 61b ... strikers, 62a, 62b ... proximity switches.

Claims (3)

[Claims] 1. A slip detector for detecting a slip on the power transmission surface of a rotational force transmission mechanism that is connected to a drive shaft and a driven shaft and transmits the rotational force of the drive shaft to the driven shaft via a power transmission surface. The drive-side detected portion provided on the drive-side rotation surface with respect to the power transmission surface, and the driven-side detected portion provided on the driven-side rotation surface with respect to the power transmission surface,
A drive-side sensor that detects the drive-side detected portion at an opposed position, a driven-side sensor that detects the driven-side detected portion at an opposed position, and a detection timing of the driven-side sensor with respect to a detection timing of the drive-side sensor. A slip detection device for a rotational force transmission mechanism, comprising a signal processing circuit for detecting a time delay. 2. The slip detection device for a rotational force transmission mechanism according to claim 1, wherein the drive side sensor and the driven side sensor are constituted by proximity switches. 3. The rotation according to claim 1, wherein the rotational phase of the driven-side detected portion is displaced from the drive-side detected portion by a predetermined amount in the initial state. Slip detector for force transmission mechanism.