JP2003184967A - Device for detecting tooth-skip in timing belt and motorized injection molder in which the device is used - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for detecting tooth-skip in an timing belt, which eliminates various malfunctions to be caused by tooth-skip in the timing belt, and provide a motorized injection molder in which the device is used. <P>SOLUTION: In the device for detecting tooth-skip in a timing belt 3 which is passed over a driving pulley 1 and a driven pulley 2, there are provided a plurality of projections 4 placed in the peripheral direction of the side face of the pulley 2, a proximity switch 5, a tooth-skip-signal generating part 7, and a controller 8. The proximity switch 5 is attached in opposition to one of the projections 4, and issues signals by detecting passage of the projection 4 associated with revolution of the pulley 2. The signal generating part 7 captures a signal issued from the proximity switch 5, and if the rate of passage of the projection 4 per unit time disagrees with a predetermined rate, a tooth- skip signal is issued to indicate occurrence of tooth-skip. The controller 8, on receiving the tooth-skip signal, stops the motor 6 driving the driving pulley 1. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timing belt tooth jump detection device and an electric injection molding machine using the same.

[0002]

2. Description of the Related Art A conventional device driven by a timing belt hung between a drive pulley and a driven pulley does not have a tooth jump detection device, and if the belt jumps for some reason, the control origin position shifts. Occurred.

[0003]

Therefore, in a device driven by a timing belt, such as an injection device of an electric injection molding machine or a mold clamping device, a die caused by an overstroke due to a displacement of a control origin is used. There was a risk of damage or malfunction.

Similarly, even in the product projecting step of taking out the product from the mold, if the timing belt has a tooth jump, the projecting pin is projected into the mold cavity where the mold is clamped due to overstroke or the like. A part of the product remains as it is, and a defective product may be produced, or the mold or the like may be damaged in the next mold clamping step.

An object of the present invention is to provide a device for detecting tooth jump of a timing belt for removing various malfunctions caused by the tooth jump of the timing belt as described above, and an electric injection molding machine using the same. To do.

[0006]

In order to achieve the above-mentioned object, the present invention relates to a tooth jump detection device for a timing belt hung between a driving pulley and a driven pulley, in which a side surface of the driven pulley is circumferentially arranged. A plurality of provided protrusions, and a contact or non-contact type sensor which is attached so as to face at least one of these protrusions and which detects the passage of the protrusions accompanying the rotation of the driven pulley and transmits a signal; A tooth of a timing belt, characterized by comprising a tooth jump signal generating section that takes in a signal from this sensor and generates a tooth jump signal when the amount of passage of a protrusion per unit time is different from a predetermined amount. It was used as a jump detector. It should be noted that instead of the protrusion, a hole may be formed, and the sensor may be configured to detect passage of the hole.

In order to achieve the above-mentioned object, the present invention is a timing belt tooth jump detection device hung between a drive pulley and a driven pulley, wherein at least one of the teeth of the driven pulley is opposed to the top. A contact or non-contact type sensor that is attached and that detects the passage of the top of the tooth due to the rotation of the driven pulley and transmits a signal, and the signal from this sensor is taken in and the amount of passage of the tooth per unit time is A tooth jump detection device for a timing belt may include a tooth jump signal generator that generates a tooth jump signal when the amount differs from a predetermined amount.

Further, in order to achieve the above-mentioned object, the present invention provides a timing belt tooth jump detection device hung between a driving pulley and a driven pulley, wherein at least one peak of the timing belt is opposed to the top. The contact or non-contact type sensor that is attached to the sensor to detect the passage of the top of the mountain due to the running of the timing belt and emits a signal, and the signal from this sensor to capture the amount of passage of the mountain per unit time. And a tooth jump signal generation unit that generates a tooth jump signal when the amount is different from a predetermined amount.

Further, a control device for stopping the motor for driving the drive pulley in response to the tooth jump signal from the tooth jump signal generating section may be further provided, and the tooth jump of the timing belt described above may be further provided. It is more preferable to use an electric injection molding machine that uses any of the tooth skip detection devices of the detection devices.

Thus, the tooth jump of the timing belt can be detected easily and accurately, and malfunction can be prevented.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
Will be described. A timing belt 3 is hung between the drive pulley 1 and the driven pulley 2. A plurality of protrusions 4 (4a, 4b, 4c) are formed on the side surface of the driven pulley 2 in the circumferential direction.
......), a proximity switch 5 is provided on a fixed portion (not shown) so as to face the top of one of the protrusions 4, and a plurality of protrusions 4a and 4b that are sequentially rotated by the rotation of the driven pulley 2 are provided. 4c ... is detected and a signal is generated. In addition, it is preferable that the protrusions 4 are provided so as to correspond to the intervals between the teeth of the driven pulley 2.

The signal from the proximity switch 5 is taken into the tooth jump signal generator 7. The tooth jump signal generation unit 7 detects the protrusions 4 per unit time which are detected and set in advance in a normal state.
Of the number of signals transmitted from the proximity switch 5, that is, the actual amount of passage of the protrusion 4 is compared, and the tooth jumping of the belt occurs, and the set value and the passage of the protrusion transmitted from the proximity switch 5 are compared. When the amounts do not match, a tooth jump signal is generated and notified, and this tooth jump signal is sent to the controller 8.
To stop the motor 6 driving the drive pulley 1.

The proximity switch 5 has a plurality of protrusions 4a,
4b, 4c, etc. are sequentially detected one by one and a signal is generated corresponding to the number of protrusions passing through. For example, the movement amount of the protrusions 4 within one pitch of the protrusions 4 is continuously and repeatedly detected. However, various detection methods can be employed, such as the passage speed of the protrusions per unit time, that is, the passage amount may be obtained in an analog manner.

Further, as shown in FIG. 2, the driven pulley 11
1 is provided with a through hole (which may be a bottomed hole) 12 instead of the protrusion 4 of FIG.
It is also possible to detect the amount of passage through the through hole 12 due to the rotation of.

Further, as shown in FIG. 3, the drive pulley 21
In the drive device for driving the timing belt 23 hung between the driven pulley 22 and the driven pulley 22 by the motor 24,
A non-contact type sensor 25 is provided so as to face the tops of the teeth of the driven pulley 22 so as to detect the number of revolutions of the driven pulley 22 per unit time. When it is detected that the rotation speed is different from the rotation speed, a tooth jump signal is generated and the control device 27 causes the motor 2 to rotate.
The driving of No. 4 may be stopped.

Next, an example of using the timing belt tooth jump detection device of the present invention in an electric injection molding machine will be described with reference to FIG. 4. In the electric injection molding machine 30, a frame 31 has an injection device 32 and a mold clamping device 33. It is equipped with. The injection device 32 is provided with a screw 37 which is rotated in a heating barrel 34 by a metering motor 35 and is moved forward and backward by a predetermined distance in an axial direction by an injection motor 36.

Driving pulleys 38, 39, driven pulleys 40, 41 and timing belts 42, 43 are provided between the metering motor 35 and the screw 37 and between the injection motor 36 and the screw 37, respectively. 5, a timing belt tooth jump detection device is attached. For example, as shown in FIG. 5, a timing belt 43 is hung between a drive pulley 39 attached to an injection motor 36 and a driven pulley 41 attached to a screw 37. On the mountain side of the same timing belt 43, the proximity switch 4 is placed so as to face the mountain top.
5 is attached.

Therefore, the timing belt 4 is caused by the tooth jump.
When the amount of movement of No. 3 per unit time is changed, it is detected that the tooth jump signal generation unit (not shown) is different from the predetermined amount of belt movement caused by the tooth jump of the timing belt 43, and the injection motor 36 It acts to stop.

Further, the mold clamping device 33 moves the movable mold 49 mounted on the movable plate 48 forward and backward with respect to the fixed mold 47 mounted on the fixed plate 46 to open and close both molds 47 and 49. That is, the mold is closed during the mold clamping step, a mold cavity (not shown) is formed, and then the molten resin is injected into the mold cavity from the injection device 32 described above.

The movable platen 48 having the movable mold 49 attached thereto is moved forward and backward by a toggle mechanism 51 provided between the support 50 and the movable platen 48.
Drive pulley 53 by the mold clamping motor 52 attached to
A screw shaft 56 attached to the driven pulley 55 by a drive system including a timing belt 54 and a driven pulley 55.
It is driven by rotating.

The drive pulley 53 and the timing belt 5
The drive system including the driven pulley 4 and the driven pulley 55 is, of course, provided with the timing belt tooth jump detection device according to the present invention, and can detect the timing belt tooth jump for some reason. .

In the embodiment described above, the sensor for detecting the passage of the protrusion or the like has been described as a non-contact type proximity switch, but the present invention is not limited to this, and a sensor that directly contacts may be used. Can be used.

[0023]

As described above, according to the present invention, it is possible to detect the tooth jumping of the timing belt by the signal generated by the proximity switch or the like, and it is possible to prevent malfunctions and the like, and the configuration thereof is simple.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a timing belt tooth skip detection device according to an embodiment of the present invention, in which (a) is a front view when a protrusion is provided on a side surface of a driven pulley, and (b) is (a). A-
FIG.

FIG. 2 is an explanatory view of a tooth jump detection device for a timing belt showing another embodiment of the present invention, and is an explanatory view showing a case where a through hole is provided in a side surface of a driven pulley.

FIG. 3 is an explanatory diagram of a tooth jump detection device for a timing belt according to still another embodiment of the present invention, which is an explanatory diagram showing a case where tooth jump detection of a timing belt is performed by detecting the rotational speed of a driven pulley. is there.

FIG. 4 is an explanatory diagram of an electric injection molding machine using the timing belt tooth jump detection device of the present invention.

FIG. 5 is an explanatory diagram of a tooth jump detection device for a timing belt showing still another embodiment of the present invention, and is an explanatory diagram showing a case where tooth jump detection of the timing belt is performed by detecting the movement amount of the timing belt. FIG. 5 is an enlarged view of arrow Z in FIG. 4.

[Explanation of symbols]

1, 21, 38, 39, 53 Drive pulley 2, 11, 22, 35, 40, 41, 55 Driven pulley 3,23,42,43,54 Timing belt 4 protrusions 5, 13, 25, 45 Proximity switch (sensor) 6, 24 motor 7, 26 Tooth skip signal generator 8, 27 Control device 12 through holes 30 Electric injection molding machine 31 frames 32 injection device 33 Mold clamping device 34 heating barrel 35 Measuring Motor 36 Injection motor 37 screws 46 Fixed board 47 Fixed mold 48 movable plate 49 movable mold 50 support 51 Toggle mechanism 52 Mold clamping motor 56 screw shaft

Claims (6)

[Claims] 1. A timing belt tooth jump detection device hung between a drive pulley and a driven pulley, wherein a plurality of protrusions provided in a circumferential direction on a side surface of the driven pulley and at least one of these protrusions. A contact or non-contact type sensor that is mounted so as to face each other and that detects the passage of the protrusion due to the rotation of the driven pulley and sends a signal, and the signal from this sensor is taken in to pass the protrusion per unit time. A tooth jump detection device for a timing belt, comprising: a tooth jump signal generator that generates a tooth jump signal when the amount is different from a predetermined amount. 2. The timing belt tooth jump detection device according to claim 1, wherein the protrusion is replaced by a hole, and the sensor is configured to detect passage of the hole. 3. A tooth jump detection device for a timing belt hung between a drive pulley and a driven pulley, wherein the timing belt tooth jump detection device is mounted so as to face at least one top of the teeth of the driven pulley, A contact or non-contact sensor that detects the passage of the top of the tooth and sends a signal, and the signal from this sensor is taken in, and a tooth jump signal is output when the amount of tooth passage per unit time is different from a predetermined amount. A tooth jump detection device for a timing belt, comprising: a tooth jump signal generation unit that generates the tooth jump signal. 4. A timing belt tooth jump detection device hung between a drive pulley and a driven pulley, wherein the timing belt tooth jump detection device is mounted so as to face at least one apex of the crest of the timing belt, A contact or non-contact type sensor that detects the passage of the top of the mountain and sends a signal, and the signal from this sensor is taken in, and a tooth jump signal is generated when the amount of mountain passage per unit time is different from a predetermined amount. A tooth jump detection device for a timing belt, comprising: a tooth jump signal generation unit that generates the tooth jump signal. 5. The controller according to claim 1, further comprising a control device that stops a motor that drives the drive pulley in response to a tooth jump signal from the tooth jump signal generator. The tooth jump detection device for a timing belt according to any one of claims. 6. An electric injection molding machine using the tooth jump detection device according to claim 1. Description: