JP2852701B2 - Method and apparatus for measuring performance of Osa for air jet loom - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial application field >> The present invention relates to an air jet loom (air jet loom).
The present invention relates to a method and an apparatus for measuring the performance of a bait for use, which is formed by cutting a leading edge of a feather wing and forming a guideway (hereinafter, referred to as a "tunnel") for guiding an air jet. And a method and apparatus for measuring.

<< Prior Art >> In an air jet loom, a large number of sub-nozzles are provided in addition to a main nozzle, and a weft in a tunnel is urged by an air jet from these sub-nozzles to fly. The air jet from the sub-nozzle is normally blown obliquely into the tunnel from below and in front of the tunnel, collides with the portion from the upper surface to the inner surface of the tunnel, is reflected, and flows along the tunnel to convey the weft. Therefore, the weft insertion performance of the air jet loom can be measured by measuring the type of air flow generated by the air jetted from the sub-nozzles in the tunnel.

The conventional method of measuring what air flow is created in the tunnel by the air jet of the sub-nozzle is to actually attach the Osa 3 to the loom or to use the Osa 3 and the sub-nozzle.
The positional relationship with the sub-nozzle 21 is made to be very similar to that of the actual loom, as shown in FIG.
The air is injected into the tunnel 4 from the pit, and immediately after the position where the center 6 of the air jet collides with the wall surface of the tunnel (the portion from the upper surface to the inner surface), the pitot tube 9 is brought close to the wall surface.
And the flow rate of the air in the tunnel 4 is measured with the pitot tube.

<< Problems to be solved by the invention >> The wall surface of the tunnel 4 is formed by the upper edge of the notch 2 provided in the wing 1
2a, the back edge 2c and the lower edge 2e (FIG. 5), and there is naturally diffusion of air from the gap between the wings. The guide performance of the air flow in the tunnel 4 is determined by the rate at which the air jet impinging on the wall surface reflects or diffuses on the upper surface 4a, the inner surface 4c, and the lower surface 4e of the tunnel. You can go. The edge surface of the notch 2 of each feather wing is inclined in a direction to restrict the air flow a flowing through the tunnel to guide the air flow along the tunnel (FIG. 6). In order to prevent the tunnel from jumping forward, the edge surface serving as the inner back surface 4c of the tunnel is inclined in the direction in which the air flow a is diffused (FIG. 7).

However, in the conventional measurement method, the flow velocity in the tunnel is measured at only one point, so that even if the balance between the reflection and diffusion of the air flow on the upper surface, the inner surface, and the lower surface of the tunnel changes, it is accurately measured. As a result, it was not possible to accurately measure the variation in the weft insertion performance of Osa. In order to solve this problem, in the above measurement, a number of pitot tubes are arranged in the tunnel, or one pitot tube is moved to each position in the tunnel, and the flow velocity distribution of the air flow in the tunnel at the measurement cross section is changed. The method of seeking is partially implemented. According to such a method, it is considered that the weft insertion performance of Osa can be measured more accurately than the method of measuring the flow velocity at only one point, but the two velocity distributions in the tunnel are still almost equal. Osa sometimes exhibited completely different weft insertion performance, and it was not possible to accurately determine the weft insertion performance of Osa.

<< Means for Solving the Problems >> In the present invention, the above-mentioned problem is solved by individually measuring the air flow guiding performance at a plurality of points 4a to 4e on the wall surface of the tunnel 4 at a certain measurement cross section. In the method of the present invention, the upper surface central portion 4a, the inner surface central portion 4c, the lower surface central portion 4e, the upper inner corner portion 4b, and the upper surface central portion 4a of the tunnel 4 are not restricted by the actual positional relationship between the tunnel 4 and the sub nozzle 21. The air jets 6a to 6e are jetted at a fixed angle and speed to a plurality of measurement points on the wall surface forming the tunnel 4, such as the lower back corner 4d, and these air jets 6a to 6e correspond to the measurement points 4a to 4e. At the position immediately after the collision with the wall surface and as close as possible to the wall surface, the flow velocity in the tunnel 4 near each of the measurement points 4a to 4e is individually measured by a flow velocity detection sensor such as a pitot tube 9a to 9e. The detection method is adopted.

As an actual measurement method, one sensor is sequentially moved to a plurality of measurement points 4a to 4e, and the direction of the air jet of the air injection nozzle is sequentially deflected to each of the measurement points 4a to 4e so that one measurement is performed. A method of measuring the flow velocity at each of the measurement points 4a to 4e with the air injection nozzle and one sensor is possible. However, this method has a disadvantage that the measurement is troublesome.

Therefore, as a more realistic method, a plurality of air injection nozzles 5a to 5e are bundled, and a direction in which the air jets 6a to 6e are directed to the respective measurement points 4a to 4e is prepared. On the other hand, a plurality of sensors 9a to 9e arranged so that the tip is located close to the tunnel wall at each of the measurement points 4a to 4e are prepared, and these are installed immediately downstream of the measurement cross section of the tunnel. Air injection nozzle 5a
To 5e, the air jets are sequentially injected, and the flow rate of the corresponding sensors 9a to 9e at that time is measured.

<< Operation >> According to the method of the present invention described above, the ratio of reflection and diffusion of the air flow at each portion of the wall surface around the tunnel 4 can be accurately measured, and the performance of guiding the air flow at each portion of the wall surface of the tunnel 4 can be measured. Is immediately detected as a difference in the measured values. Therefore, the two Osa having the same measurement value measured by the above-mentioned method show exactly the same weft insertion performance, and the identity of the weft insertion performance can be accurately measured. Of course, the two mats to be compared in this case are based on the premise that the cross-sectional shape of the tunnel 4, the thickness of the mating wing 1 and the interval between the mating wings 1 are the same.

Then, the measurement of the penetration by the above-mentioned method is performed by connecting the plurality of nozzles 5a to 5e having the injection holes toward the respective measurement points 4a to 4e on the wall surface of the tunnel 4 and the air supply source 7 to the plurality of nozzles 5a to 5e. Accurate and efficient operation can be achieved by using a switching device 8 for sequentially switching and a measuring device provided with flow velocity detecting sensors 9a to 9e arranged so as to take positions close to the measuring points 4a to 4e.

<< Embodiment >> FIGS. 1 to 4 show one embodiment of the present invention, in which 1 is a wing, 2 is a cutout provided at the front edge of the wing,
Reference numeral 3 denotes an Osa formed by a set of many Osa feathers 1;
Is a tunnel formed by a set of notches 2, 4a is the upper surface of the tunnel, 4c is the inner surface, 4e is the lower surface, 4b is the upper and lower corner of the tunnel, and 4d is the lower and inner corner.

5a to 5e are nozzles provided with air injection holes at the tip.
The independent nozzles of the book are bundled so that they can be inserted into the center of the tunnel 4, and the air jets 6a to 6e form the upper surface center 4a, the lower surface center 4e, the upper back corner 4b, the back center 4c and the lower back in the same cross section of the tunnel. The tip is bent so as to face the corner 4d. Pressurized air is supplied to the nozzles 5a to 5e from an air supply source such as a blower 7.
A flow path switch 8 is provided between 5a to 5e so as to supply pressurized air to only one of the nozzles 5a to 5e.

Reference numerals 9a to 9e denote pitot tubes.
It is arranged so as to be located as close as possible to the upper surface center 4a, the lower surface center 4e, the upper back corner 4b, the back surface center 4c, and the lower back corner 4d of the peripheral wall. The positional relationship between the tips of the pitot tubes 9a to 9e is maintained by a holder 10 that holds the base of each of the pitot tubes 9a to 9e at a position away from the tunnel 4. The pitot pipes 9a to 9e are connected to a differential pressure detector 12 via a flow path switch 11, and the pitot tube side flow path switch 11 and the nozzle side flow path switch 8 are linked to each other. It is convenient if you can switch.

At the time of measurement, the flow path switches 8 and 11 are switched to supply air to a selected one of the nozzles 5a to 5e, and one of the pitot tubes 9a to 9e corresponding to the nozzle is connected to the differential pressure detector 12. Connecting. And the flow path switches 8 and 11
Are sequentially switched to measure the flow velocity in the tunnel 4 at each of the measurement points 4a to 4e. The value of the measured flow velocity reflects the ratio of reflection and diffusion of the air flow on the wall surface at each measurement point of the tunnel, and where the reflectance is large, the air flow velocity is also large.

By measuring a plurality of bosses manufactured as having the same weft insertion performance by the above method and comparing the measured values of the flow velocity at each of the measurement points 4a to 4e on the tunnel wall, if the measured values are equal, These wefts show the same weft insertion performance, and if the flow velocity at the measurement point is different even at one point, the weft insertion performances of those wools will be different. Therefore, after actually performing weft insertion with Osa designed as having certain weft insertion performance and confirming its performance,
By measuring the flow velocity distribution along the wall surface with the above-mentioned method, and checking the similarity of the flow velocity distribution by the above-mentioned measurement with respect to the manufactured Osa, it is easy to determine whether these Osa have the same weft insertion performance. And it can be determined accurately.

<< Effects of the Invention >> As described above, according to the method of the present invention, it is possible to accurately determine whether or not a desired weft insertion performance has been obtained without performing a weft insertion test on each manufactured Osa. Can be measured. Further, the use of the apparatus of the present invention has an effect that the method of the present invention can be easily implemented.

[Brief description of the drawings]

1 to 4 show one embodiment of the present invention.
1 is a perspective view of a main part showing a measurement state, FIG. 2 is a front view, FIG. 3 is a sectional view of a part A in FIG. 2, and FIG. 4 is B in FIG.
It is a fragmentary sectional view. 5 to 7 are views showing cutout portions of the feather wings. FIG. 5 is a side view, and FIG.
FIG. 7 is a sectional view of a part D in FIG. FIG. 8 is a perspective view showing a conventional method. In the figure, 3: Osa, 4: Tunnel 4a-4e: Measurement point, 5a-5e: Nozzle 6a-6e: Air jet, 9a-9e: Pitot tube

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) D03J 1/24 D03D 47/28-47/38 D03D 49/62 G01P 5/16

Claims (2)

(57) [Claims] A plurality of measurement points (4) at the same cross-section on the wall surface of a weft guide path (4) formed in a mat (3).
Air jets (6a) to (6e) were jetted individually at a fixed angle and speed toward a) to (4e), and these air jets collided with the wall of each measurement point (4a) to (4e) A method for measuring the performance of an Osa for an air jet loom, characterized by individually measuring the flow velocity in the guide path (4) at a position immediately adjacent to the wall surface. 2. A plurality of air injection nozzles (5a) to (5e).
And the direction of the air jets (6a) to (6e) is directed to a plurality of measurement points (4a) to (4e) at the same cross-section on the wall surface of the weft guide path (4) formed on the mat (3). Point the nozzle group and the tip to each of the above measurement points (4a) to (4e)
And a plurality of flow rate detection sensors (9a) to (9e) arranged so as to be located close to the wall surface of the guideway of (1).