JPH0613794Y2 - Valve seat holding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a device for holding a valve seat during the mounting of the valve seat, while the valve seat supplied from a parts supply device is transferred to a work. .

(Prior Art) Conventionally, when fitting a valve seat into a mounting hole of a work, a press-fitting bar having a valve seat holding device at its tip is used, and the press-fitting bar is initially in an upright state (horizontal state). When receiving the valve seat and holding it, the valve seat turns 90 degrees around the base point of the bottom to change the direction horizontally (downward), and its tip faces the mounting hole of the work, and the tip of the press-fit bar into the mounting hole. It is done by pushing. In the holding device provided at the tip of the press-fitting bar, the shaft diameter on the tip end side of the press-fitting bar 50 has a small diameter as shown in the longitudinal sectional view of FIG. 4, and therefore, the step portion 51 is formed on the outer peripheral surface. The small-diameter shaft 52 is provided with a screw hole 53 penetrating the diameter on a surface perpendicular to the axial direction, and a ball plunger 54 is screwed into the screw hole 53. A groove 55 is provided at the bottom. The ball plunger 54 has a seat holding ball 57 with a spring 56 interposed therein, and the seat holding ball 57 is biased outward. The screwing of the ball plunger 54 and the screw hole 53 is carried out by utilizing the groove 55, and is adjusted so that a part of the spherical body of the seat holding ball 57 projects onto the outer peripheral surface of the shaft portion having a small diameter. Has been done. In such a holding device, when the valve seat 58 is supplied onto the seat holding ball 57 of the small-diameter shaft portion, the rear surface is brought into contact with the stepped portion 51, and one point of the inner peripheral surface in the width direction approximately at the center thereof is set. It was pressed and held by the sheet holding balls 57 and transferred to the attachment hole 59 of the work.

(Problems to be solved by the invention) However, in the conventional case, there is only one pressing point for holding the valve seat, and the pressing is point contact near the widthwise center of the inner peripheral surface. Therefore, there is a problem in that the holding force is weak, and particularly when the receiving bar rotates, it tends to come off in the front direction. Moreover, as shown in FIG. A gap g is formed between the outer peripheral surfaces of the small-diameter shafts so that the valve seat 56 deviates from the central axis to one side, and even if the central axis of the mounting hole 59 and the central axis of the press-fitting bar 50 are aligned, the valve seat 58 is nicked or caught at the time of press-fitting. There was a problem that it would collapse due to. Even if an attempt is made to add a ball plunger 54 to the screw hole 53 at the other end in order to eliminate this bias, the ball plunger 55 cannot be attached due to its structure such as the position.

(Means for Solving the Problem) For this reason, in the valve seat holding device provided at the tip of the press-fitting bar, an elastic floating bar extending from the axial center of the press-fitting bar and a seat holder which is connected by inserting the floating bar. The sheet holder and the front surface of the press-fitting bar are brought into spherical contact with each other. Then, a step portion is formed on the outer peripheral surface of this sheet holder, and the tip is made to be a small diameter shaft from this step portion, and at least three or more radial openings are equally spaced along the circumferential direction of the small diameter shaft. Hollow holes were provided, and each hollow hole was internally provided with a seat holding ball that was biased outward by a spring so that a part of the sphere of the seat holding ball was projected onto the outer peripheral surface. The valve seat supplied to the small-diameter shaft is sandwiched between the apex rear part of the protruding seat-holding ball and the step, and a circle is formed between the outer circumference of the ball-holding sleeve fitted on the small-diameter shaft and the inner circumference of the valve seat. It is configured such that it is held with a substantially uniform gap in the circumferential direction.

(Function) Since the seat holding balls for pressing and holding the inner peripheral surface of the valve seat have a plurality of pressing portions and are arranged at equal intervals, the rearward component force acting on the valve seat acts evenly and the outer peripheral surface of the small diameter shaft. A uniform gap is formed between the inner circumference of the valve seat and the inner circumference. Therefore, the valve seat is not biased with respect to the center axis of the press-fitting bar, and problems such as galling or falling down during press-fitting are eliminated. Also, when the axis of the valve seat mounting hole (press-fit hole) is misaligned parallel to the axis of the press-fit bar,
The eccentricity of the valve seat can be automatically adjusted within this gap. Moreover, since the front edge portion of the inner peripheral surface of the valve seat is pressed by the spherical rear portion of the seat holding ball, a horizontal component force that pushes the valve seat rearward acts to ensure the holding.

Further, since the floating bar connecting the sheet holder is made of an elastic body and the sheet holder and the press-fitting bar are in spherical contact with each other, the seat holder at the tip of the press-fitting bar can swing about the central portion of the joint surface with the press-fitting bar. Therefore, when the seat holder holding the valve seat is press-fitted into the mounting hole, even if the axis of the valve seat mounting hole (press-fitting hole) is bent with respect to the axis of the press-fitting bar due to some influence, The seat holder follows the mounting hole, and can prevent problems such as galling or falling of the valve seat.

(Example) This example will be described with reference to the accompanying drawings. First
1 to 3 show an embodiment of a valve seat holding device of the present invention, FIG. 1 is an overall view of a valve seat mounting device, FIG. 2 is a longitudinal sectional view of the holding device of the present invention, and FIG. FIG. 4 is a front view taken along the line AA of FIG. As shown in FIG. 1, the valve mounting device 1 includes a press-fitting bar 3 that rotates from an upright state to a horizontal state about a rotation shaft 2, and a valve seat mounting device 4 is provided at the tip of the press-fitting bar 3. It is provided. The valve seat 5 is supplied from a parts supply device (not shown) to the tip of the receiving bar 3 in the upright state, that is, the holding device 4, and the valve seat 5 held by the holding device 4.
Is changed in position by the rotation of the receiving bar 3 and faces the mounting hole 6a of the work 6, and is pressed into the mounting hole 6a by the pushing motion of the press-fitting bar 3.

As shown in FIG. 2, the holding device 4 has a seat holder 7 for holding the valve seat 5 separated from the press-fitting bar 3, and the seat holder 7 is provided with a shaft hole 7a in its central axis. On the other hand, an elastic floating bar 8 projecting in the axial direction from the shaft center of the press-fitting bar 3 is provided integrally with the press-fitting bar 3, into which the shaft core hole 7a of the seat holder 7 is inserted to lock the front surface. The members 8a are connected so that they cannot be pulled out. The contact surface between the press-fitting bar 3 and the seat holder 7 is slidable spherically, that is, the press-fitting bar 3 side is formed into a spherical concave shape, and the sheet holder 7 side is formed into a spherical convex shape.

A step portion 9 is provided on the outer peripheral surface of the seat holder 7, and a tip of the step portion forms a small diameter shaft 10. The four portions on the surface perpendicular to the axial direction of the small diameter shaft 10 face outward. Hollow holes 11 that open are provided at equal intervals in a radial pattern. A seat holding ball 13 with a spring 12 interposed therein is urged outward in the hollow hole 11 and is internally mounted. A part of the sphere of the seat holding ball 13 passes over the seat holding ball 13 from the tip. By engaging with the side end portion 14a of the fitted ball holding sleeve 14, only a part of the spherical body is projected onto the outer peripheral surface. The ball holding sleeve 14 is fixed by a positioning pin 15 in order to prevent the ball holding sleeve 14 from rotating or coming out forward.

The outer diameter of the ball holding sleeve 14 is slightly smaller than the inner diameter of the valve seat 5, as shown in FIG.

In this holding device 4, the valve seat 5 is fed over the seat holding balls 13, the rear surface is brought into contact with the outer peripheral surface step portion 9 and the inner peripheral surface front edge portion of the front surface is the apex of the four seat holding balls 13. It is held at the rear part and transferred to the attachment hole 6a of the work 6.

At this time, the seat holding ball 13 is attached to the valve seat 5.
The rearward component force exerted by is uniform, so that a uniform gap is formed between the outer circumference of the ball holding sleeve 14 and the inner circumference of the valve seat 5 along the circumferential direction.

Therefore, for example, even when the axis of the mounting hole 6a is misaligned in parallel with the axis of the press-fitting bar 3, the valve seat 5 can be automatically eccentrically adjusted within the range of this clearance, and the mounting hole 6a can be adjusted.
Even when the axis of a is bent with respect to the axis of the press-fitting bar 3, the elastic bending action of the floating bar 8 and
Due to the spherical surface contact of the front surface of the press-fitting bar 3, there is no problem such as galling or falling.

The number of seat holding balls attached is arbitrary, but it is effective to hold the seat holding balls with at least three seat holding balls in order to ensure the holding. Further, by selecting a material having a low elastic modulus that does not hinder the press-fitting as a material of the floating bar, it is possible to cope with a large deviation of the central axis. Needless to say, the contact surface of the spherical surface receiving surface may have unevenness.

(Effects of the Invention) With the above-described configuration, the valve seat holding device of the present invention eliminates the problem that the valve seat falls off due to insufficient holding force until it is transferred to the work mounting point in the related art. It has become possible to improve the work efficiency by eliminating the troubles that have occurred when press-fitting into the mounting holes, that is, the troubles such as galling or falling due to the eccentricity of the held valve seat. Furthermore, it is effective in terms of not damaging the valve seat when the valve seat is attached, and has an effect in terms of quality improvement.

[Brief description of drawings]

1 to 3 show an embodiment of a valve seat holding device of the present invention. FIG. 1 is an overall view of a valve seat mounting device, and FIG. 2 is a vertical sectional view of a valve seat holding device. 3 is a front view taken along the line AA of FIG. 2, FIG. 4 is a longitudinal sectional view showing a conventional holding device, and FIG. 5 is the same front view. In the drawings, 1 is a valve mounting device, 2 is a rotary shaft, 3 is a press-fitting bar, 4 is a holding device, 5 is a valve seat, 6 is a work,
6a is a mounting hole, 7 is a seat holder, 7a is a shaft core hole, 8
Is a floating bar, 8a is a locking member, 9 is a step, 1
0 is a small diameter shaft, 11 is a hollow hole, 12 is a spring, 13 is a seat holding ball, 14 is a ball holding sleeve, and 14a.
Is a side end portion, 15 is a positioning pin, 50 is a press fitting bar, 51
Is a stepped portion, 52 is a small diameter shaft, 53 is a screw hole, 54 is a ball plunger, 55 is a groove, 56 is a spring, 57 is a seat holding ball, 58 is a valve seat, 59 is a mounting hole, g
Indicates a gap.

Claims (1)

[Scope of utility model registration request] 1. A valve seat holding device provided at the tip of a press-fitting bar, wherein the holding device is connected to an elastic floating bar extending from the axis of the press-fitting bar and the front face of the press-fitting bar by inserting the floating bar through the floating bar. A seat holder that is in spherical contact with the seat holder is provided, and a step portion is formed on the outer peripheral surface of the seat holder, and the tip of the step portion has a small diameter axis, and at least 3 at equal intervals along the circumferential direction of the small diameter axis. Hollow holes that are radially opened at more than one place are provided, and each of the hollow holes is internally provided with a seat holding ball that is biased outward by a spring so that a part of the sphere of the seat holding ball is projected onto the outer peripheral surface. A ball holding sleeve fitted to the small diameter shaft, which is sandwiched between the apex rear portion of the seat holding ball projecting the valve seat supplied to the small diameter shaft portion and the step portion, and A valve seat holding device is characterized in that so as to retain substantially to have a uniform gap throughout the circumferential direction between the inner peripheral Rubushito.