JP4594518B2 - Dispersion device for powder for sintering on back metal - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a spraying device for spraying a sintered metal, an inorganic compound or a resin powder in addition to these on a back metal.
[0002]
[Prior art]
For example, Japanese Patent No. 2849928 relating to the production of a sliding bearing alloy shows the above-mentioned powder dispersion. In the sintering method using such an apparatus, conventionally, a straight bar is brought into contact with the surface of the powder spreading layer so that the dispersed powder layer has a constant thickness in the width direction of the back metal, and the thickness is leveled. It was.
[0003]
The continuous strip-shaped coil is rewound flat, and then is corrected by passing through a roller group that alternately performs U-shaped bending and reverse U-shaped bending in order to take up winding. Since the coil is heated to the sintering temperature after the powder is sprayed, the distortion in the coil state is released and softened and annealed, so correction is not necessary for the purpose of flattening the back metal, but uniform spraying. Correction is required to obtain thickness.
The case where the cross section of the back metal after correction warps in a concave shape will be described with reference to FIG. 1, and the case where the back surface warps in a convex shape will be described with reference to FIG. In the figure, 1 is a back metal, 16a is a powder layer, 30 is a straight bar, and 31 is a base roll. In each figure, the surface of the powder is scraped by the straight bar 30 to become a flat surface (FIGS. )). After scraping, the back metal 1 is flattened through heating by primary and secondary sintering, compression between them, etc., so if the cross section of the back metal is concave and convex in the state of FIG. (B) As shown in the figure, the surface of the powder layer 16a is convex and concave.
[0004]
[Problems to be solved by the invention]
As described above, when the powder layer on the continuous belt-like backing metal is scraped with a straight bar, it is difficult to achieve a certain powder layer thickness if the backing metal is warped. Therefore, the present invention is applied to a method of spreading powder on a continuous belt-like backing metal and then sintering, and provides a spreading device capable of forming a sintered layer having a uniform thickness distribution in the width direction. Objective.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a conveying means for sending a continuous belt-like backing metal in the length direction, a spreading means for spreading powder in the width direction on the continuous belt-like backing metal being conveyed, Thickness measuring means for measuring the thickness of the powder layer dispersed on a continuous belt-like backing metal in a non-contact manner at least at the center and both ends in the width direction, and comparing the thickness of the powder layer with a set value. It is located between the means for calculating the difference, the spraying means and the thickness measuring means and is in sliding contact with the surface of the powder layer to level the surface of the powder layer, and the vertical position and shape of the sliding contact surface can be changed. The present invention provides an apparatus for spraying powder for sintering onto a back metal, comprising a thickness leveling means and a means for correcting the position or shape of the thickness leveling means so as to correct the difference. Hereinafter, the present invention will be described in detail with reference to the drawings.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 3, a back metal 1 made of, for example, a steel plate is conveyed in a line traveling direction indicated by an arrow. A recoiler for applying a main driving force for conveying the back metal 1 and an uncoiler around which the back metal coil is wound are not shown. These recoilers and uncoilers are controlled in rotation speed so that the back metal 1 is conveyed at a constant speed in the range of, for example, 2.5 to 2.7 m / min. The backing metal 1 is an uncoiler by alternately performing U-shaped bending and reverse U-shaped bending by meandering at least once through a leveler 2 composed of a roller group in which driving rollers and idle rollers are appropriately combined. Curling wrinkles in the wound state are corrected. 5 is a leveler box, and 6 is a support structure.
[0007]
Leveler 2 roller group (
1276236923365_0
The bending applied to the back metal 1 by the three rollers 2a, 2b, and 2c on the exit side in the conveyance direction affects the cross-sectional profile in the width direction (in this paragraph and the next paragraph, it is simply referred to as “profile”). give. The profile of the back metal 1 depends on the storage conditions of the coil in addition to the manufacturing conditions such as the amount of C, the thickness, and the coiling temperature that control the properties of the steel sheet coil, that is, the quench hardening ability. Are often inverted U-shaped or opposite U-shaped. In addition, many back metal which went through the correction which performs bending with a curvature radius of 0.2-3 m 6 times in the leveler group 2 had an inverted U-shaped profile with a curvature radius of 7-150 m. When powder is spread on the back metal 1 as it is,
1276236923365_1
Ing as. According to the spraying device of the present invention, the above method can theoretically make the thickness almost constant regardless of the profile, but it is desirable to make the profile flat before powder spraying. For this purpose, the amount of warping of the profile is measured by the laser type distance meter 3, and hydraulic pressure reduction control is performed so as to reduce the warpage. The profile can be made nearly flat by increasing the amount of bending of the reverse U-shaped profile back metal 1 by the roller group. And if the profile be such control does not approach flattened itself or profiles also be a U-shape, while maintaining the correct amount of bending, of the powder layer by equalizing Atsubo scatter apparatus of the present invention Flattening can be achieved.
[0008]
On the exit side of the leveler 2, a roller provided below the laser distance meter 3 supports and slides the back surface of the back metal 1. At least three distance measuring instruments 3 are arranged in the back metal width direction, and a back cross-sectional shape profile is calculated from D _c , D _r, D _l from at least three distance measurement values obtained by these distance measuring instruments 3. Where D is the distance, and subscripts c, r, and l are the center, left, and right, respectively. In most cases, after the back metal 1 passes through the leveler 2, D _r ≈D _l , and both ends of the back metal are at the same level and are flat. Assuming that the distance meter 3 is on the back metal 1, if D _r > D _c and D _l > D _c, it is a middle convex, if D _r <D _c and D _l <D _c , a middle concave, D _r If <D _c <D _l or D _l <D _c <D _r , it is inclined. In some cases, D _r >> D _l or D _r << D _l and the line connecting the both ends of the back metal is inclined as shown in FIGS. 4A and 4B, so that the whole is flat on the basis of the inclined line. (Warpage amount = 0) or the amount of unevenness, that is, the amount of warpage is calculated.
[0009]
Powder 16 such as a copper alloy (see FIG. 3) is stored in the powder supply hopper 13 and is once sent to the powder wide hopper 14 through the flow guide tube 15. As a result, the powder 16 is dispersed in the width direction of the back metal 1 through the wide slit 17 as shown in FIG. 5 to form a powder layer 16a. The powder wide hopper 14 may be provided with a driving means and / or a movable sieve (not shown) to promote the fall of the powder. 3 is a roller for supporting the back metal 1 from below.
[0010]
The thickness of the powder 16 spread on the backing metal 1 is leveled as described later by a leveling rod 24 (FIGS. 3 and 5) made of a flexible material such as stainless steel / rubber. The thickness of the powder layer 16a is measured by a non-contact type thickness measuring device 20 such as a laser measuring device. This non-contact type measuring device 20 measures the total thickness of the back metal 1 and the powder layer 16a at three positions of both end portions (a, c) and the central portion (b) and at the top and bottom.
[0011]
The thickness of the powder layer 16 a (see FIGS. 5 to 7) is leveled by the leveling rod 24. The thickness is adjusted by moving up and down the three cylinders 25a, b, and c over the entire thickness equalizing rod 24. When the back metal 1 is warped convexly as shown in FIG. 8, the surface of the powder layer 16 a is adjusted to the same shape as the same warp of the back metal 1 by pulling up the center of the thickness equalizing rod 24 by the cylinder 25 b. On the other hand, when the back metal 1 warps in a concave shape as shown in FIG. 9, the surface of the powder layer 16a is adjusted to the same shape as the same warp of the back metal 1 by pulling up both ends of the thickness equalizing rod 24 by the cylinders 25a and 25c.
[0012]
As shown in FIG. 10, the thickness control described above is performed by comparing the thickness target value with the thickness target value after soaking, and if they match, the position or deflection of the soaking bar is maintained as it is, If they do not match, the position of the leveling bar is corrected by the amount of mismatch.
[0013]
In the present invention,
1276236923365_2
As shown, it is preferable to feedback control the bending force of the roller group so as to eliminate the warp amount of the back metal measured by the distance meter 3.
1276236923365_3
Shows an example of performing this feedback control by on-off control. Since the profile shown in (a) of FIG. 6 is initially reverse U, when the bending force of the roller group is increased (ON), the profile gradually becomes flat, so when the profile returns to the allowable range. Makes the bending force of the roller group normal (off). This onoff operation is repeated. Of course, PID control can be performed in addition to onoff control. Even when the back metal shape cannot be corrected by performing these controls, a sintered layer having a uniform thickness distribution in the width direction can be formed by the thickness control in the spraying device of the present invention .
[0014]
It is possible to perform feedforward control for deforming the thickness equalizing rod 24 in accordance with the amount of warpage measured by the distance meter 3. In this case, theoretically, the surface of the powder layer 16a becomes flat after spreading, but the theoretically predicted result may not be obtained due to factors such as variations in the plate thickness and width of the continuous belt-like coil. Feedback control can be used together.
[0015]
A raw material is manufactured through the process of temporary sintering and compression after powder dispersion | distribution, main sintering, and compression. This material is cut and finally bent into a semicircular arc shape to produce half metal, bush, washer and the like.
[0016]
【Example】
When the apparatus shown in FIG. 3 was used to perform hydraulic pressure reduction control by feedback, feed forward, and thickness control rod shape control by feedback, copper alloy powder (target layer thickness) was placed on a back metal 1 having a thickness of 1.5 mm and a width of 250 mm. When the thickness dispersion (3σ) in the width direction of the back metal was 10 μm was obtained.
[0017]
【The invention's effect】
As described above, according to the present invention, since the thickness of the powder layer dispersed in a continuous band backing metal can be made uniform in the width direction of the backing metal, the performance of the final sintered product can be stabilized. Become.
[Brief description of the drawings]
FIG. 1 is an explanatory view of a conventional method for scraping off powder spread on a U-shaped backing metal, (a) shows a scraped state, and (b) shows a powder layer after spreading.
FIGS. 2A and 2B are explanatory diagrams of a conventional method of scuffing powder spread on a reverse U-shaped backing metal, FIG. 2A shows a scraped state, and FIG. 2B shows a powder layer after spraying.
FIG. 3 is a drawing showing an embodiment of the spraying device of the present invention .
4 is graphs (a) and (b) showing the inclination in the back metal width direction on the exit side of the leveler 2 shown in FIG. 3. FIG.
FIG. 5 is an enlarged perspective view of the powder spreading unit in FIG. 3;
FIG. 6 is an explanatory view of the lifting / lowering operation of the thickness uniforming means.
FIG. 7 is an explanatory diagram of a situation where the thickness of the powder layer is leveled by the thickness leveling means.
FIG. 8 is an operation explanatory view of the thickness-equalizing means when the back metal is warped in a U-shape.
FIG. 9 is an explanatory view of the operation of the thickness-equalizing means when the back metal is warped in an inverted U shape.
FIG. 10 is a flowchart of a spray layer thickness control method.
FIG. 11 is a flowchart of a method for controlling the profile of the back metal cross section on the leveler group extraction side.
FIGS. 12A and 12B are diagrams illustrating an example in which the control of FIG. 11 is performed by on-off control. FIG. 12A shows a change in profile, and FIG. 12B shows a change in bending force of the leveler at the final position.
[Explanation of symbols]
1 Back metal 2 Leveler 3 Distance meter 13 Powder barrel 14 Powder wide hopper 16 Powder 20 Non-contact type thickness meter 24 Thickness bar

Claims (4)

 Conveying means for sending the continuous belt-like backing metal in the length direction, spraying means for spreading powder in the width direction on the continuous belt-like backing metal being conveyed, and a powder layer dispersed on the continuous belt-like backing metal being conveyed A thickness measuring means for measuring the thickness in a non-contact manner at least at the center and both ends in the width direction, a means for calculating a difference by comparing the thickness of the powder layer with a set value, and Positioning means between the spraying means and the thickness measuring means to slidably contact the surface of the powder layer and level the surface of the powder layer, and a thickness leveling means capable of changing the vertical position and shape of the slidable contact surface, An apparatus for spraying powder for sintering onto a back metal comprising means for correcting the position or shape of the thickness-uniforming means so as to correct the difference. Correcting means comprising a group of rollers that alternately perform U-shaped bending and reverse U-shaped bending in a direction perpendicular to the length direction while conveying the continuous belt-like backing metal, and the continuous after the correction and before the powder application means a powder for sintering of the measured and means for controlling the amount of bending by the correcting means so that the warpage amount is reduced and becomes further comprise claim 1, wherein measuring the warpage of the width direction of the belt-like backing Spraying equipment. The spraying device of the powder for sintering on the back metal according to claim 2, wherein the correction means is feedback-controlled by the warp amount measured by the warp amount measuring means. The apparatus for spraying powder for sintering onto a back metal according to claim 2, wherein the thickness-equalizing means is feedforward controlled by the warpage amount measured by the warpage amount measuring means.

Images