JPH0332541Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a pump abnormality detection device for detecting an abnormality in a pump for supplying pressurized water for weft insertion in a water injection loom.

<Prior Art> FIG. 2 shows a conventional example of a pressure water feeding device for a water jet loom, and FIG. 3 shows the internal structure of a pump in the same feeding device.

Referring to FIG. 2, reference numeral 1 is a constant water level aquarium in which the water level is always kept constant.

2 is a reciprocating pump, usually a plunger pump is used, and as shown in FIG.
This causes the plunger 4 to move to the right in the figure to perform the suction stroke, and then the spring 5 causes the plunger 4 to move to the left in the figure to perform the discharge stroke. Ball valves 6 and 7 are provided as one-way valves on the suction side and the discharge side of the pump 2, respectively.

The water tank 1 and the ball valve 6 on the suction side of the pump 2 are connected through a pipe 8, and the ball valve 7 on the discharge side is connected through a pipe 9 to a weft insertion nozzle 11 on the frame 10. A weft yarn 13 from a weft gripper 12 is passed through the weft insertion nozzle 11.

Therefore, during the suction stroke by the cam 3 of the pump 2, the ball valve 7 on the discharge side closes and the ball valve 6 on the suction side opens to suck water from the water tank 1 through the pipe 8, and the spring 5 In the discharge stroke, the water pressure closes the ball valve 6 on the suction side, opens the ball valve 7 on the discharge side, and supplies pressurized water to the weft insertion nozzle 11 via the pipe 9. The weft yarn 13 is inserted into the warp opening along with the water jet from the weft.

<Problems to be solved by the invention> However, in the case of the pump 2 having such a structure, the ball valve 6 on the suction side is strongly hit against the valve seat part by the pressure water during the discharge stroke. Alternatively, the valve seat may be severely worn, and this wear may cause pressure water to flow back slightly toward the water tank 1 side, lowering the pressure of the pressure water sent to the weft insertion nozzle 11, thereby preventing weft insertion errors. This may occur.

Since this phenomenon is rare in the early stages of wear, it is treated as a simple weft insertion error, and even if it occurs more frequently, it is difficult to discover that the cause is the ball valve 6 of the pump 2. It was hot.

Therefore, an object of the present invention is to make it possible to easily discover abnormalities in the pump due to wear of the one-way valve on the suction side of the pump.

<Means for solving the problem> For this reason, the present invention includes a pressure detector that detects the pressure in the waterway from the water tank to the reciprocating pump, and a system in which the pressure detected by the pressure detector exceeds a reference value. To provide a pump abnormality detection device comprising an abnormality detector that outputs an abnormality detection signal when the abnormality is exceeded.

<Operation> If the pressure in the waterway from the water tank to the reciprocating pump is detected in this way, if backflow occurs during the discharge stroke due to wear or damage to the one-way valve on the suction side of the pump, the pressure in the waterway will be detected. As the pressure increases, by detecting that it exceeds the standard value and outputting an abnormality detection signal, it is possible to indirectly detect abnormalities in the pump due to wear of the one-way valve on the suction side of the pump, etc. can.

<Embodiment> An embodiment of the pump abnormality detection device according to the present invention will be described below with reference to FIG.

A pipe 8 (see Fig. 2) forming a water channel from the water tank 1 to the reciprocating pump 2 is made of an elastic material such as nylon resin, and a piezoelectric element 20 as a pressure detector is attached to the outer wall of the pipe 8 (see Fig. 2). Element 2
A rigid ring-shaped holder 21 is fitted to the pipe 8 including the pipe 8.

The output of the piezoelectric element 20 is connected to an arithmetic circuit 22 as an abnormality detection device. This arithmetic circuit 22 compares the output from the piezoelectric element 20 with a reference value from a reference value output circuit 23, and outputs an abnormality detection signal when the output exceeds the reference value.

Next, the action will be explained.

Since the pipe 8 is an elastic body, when there is a backflow as described above, the internal pressure temporarily increases, so that the pipe 8 expands and strongly presses the piezoelectric element 20 against the holder 21 .
Then, the strain of the piezoelectric element 20 increases, and its output increases. Therefore, this output is the arithmetic circuit 2
Compare with the standard value in 2 and if it is larger than this,
It outputs an abnormality detection signal. This abnormality detection signal is used to turn on a warning light or stop the loom.

The pressure detector may be provided outside the waterway to indirectly detect the pressure in the waterway as in this embodiment, but it may also be provided inside the waterway to directly detect the pressure.

<Effects of the invention> As explained above, according to the invention, abnormalities in the pump due to wear or damage of the one-way valve on the suction side of the pump can be indirectly but accurately detected, making it easier to discover abnormalities. is obtained.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a pump abnormality detection device showing an embodiment of the present invention, Fig. 2 is a perspective view of a pressure water supply device in a water jet loom showing a conventional example, and Fig. 3 is a diagram showing the same as above. FIG. 3 is a cross-sectional view of the pump in the device. 1...Aquarium, 2...Reciprocating pump, 6,7...
Ball valve, 8...Pipe, 11...Weft insertion nozzle, 20...Piezoelectric element, 22...Arithmetic circuit.

Claims (1)

[Scope of utility model registration request] The water sucked from the water tank 1 through the one-way valve 6 by the reciprocating pump 2 is fed to the weft insertion nozzle 11 as pressure water, and the weft 13 is inserted together with the water jet from the weft insertion nozzle 11. In a jet loom, a pressure detector 20 detects the pressure in a water channel 8 from a water tank 1 to a reciprocating pump 2, and an abnormality detection signal is sent when the pressure detected by the pressure detector 20 exceeds a reference value. Anomaly detector 2 that outputs
2. A pump abnormality detection device for a water jet loom, comprising: