JPH11197949A - Static pressure screw and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a static pressure screw and a manufacturing method for the static pressure screw by which a pocket can be worked precisely, simply and quickly. SOLUTION: A nut member where a screw is formed inside is divided in a plane to form a first half part 100 and a second half part. A pocket 6 to which a pressure fluid is supplied is formed on a screw surface 1a of the divided first half part 100. The first half part 100 and the similarly made second half part are superposed to be fixed in a body. The nut member is thus divided into two parts, so that the screw surface 1a is exposed to the outside, and the pocket 6 can be worked precisely, simply and quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a hydrostatic screw and a method for manufacturing a hydrostatic screw.

[0002]

2. Description of the Related Art Conventionally, a hydrostatic screw is formed by cutting a screw on an inner surface of a ring member and intermittently forming a pocket on a screw surface of the screw. Then, a pressurized fluid is supplied to the pocket, and the screw shaft screwed to the nut is supported by static pressure.

[0003]

However, in the above-described conventional hydrostatic screw, it is extremely difficult to precisely machine the pocket because it is necessary to form the pocket intermittently on the inner thread surface of the ring member. Therefore, there is a problem that the man-hour is required.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a hydrostatic screw and a method of manufacturing a hydrostatic screw which can process a pocket precisely, easily and quickly.

[0005]

According to a first aspect of the present invention, there is provided a hydrostatic screw according to the first aspect of the present invention, wherein a first half-split component having a pocket formed in a threaded surface thereof and a fluid passage formed in the threaded surface. It is characterized by comprising a second half-split part having a pocket communicating with the passage, and a fixing member for integrally fixing the first half-split part and the second half-split part.

The hydrostatic screw according to the first aspect of the present invention is divided into a first half-split part and a second half-split part. Therefore, the pocket can be machined precisely, easily and quickly on the threaded surfaces of the first and second half-split parts in the state of being divided into two.

According to a second aspect of the present invention, there is provided a method for manufacturing a hydrostatic screw.
Dividing a nut member having an internally threaded portion into a first half-split component and a second half-split component in a plane; and forming a pocket in the threaded surface of the first and second half-split components. Positioning the first half-split part and the second half-split part and fixing them together.

[0008] In the method for manufacturing a hydrostatic screw according to the second aspect of the present invention, the nut member having the screw formed on the inner side is formed in a first plane.
It is divided into a half-split part and a second half-split part. By doing so, the screw surface inside the nut member is exposed to the outside as the screw surface of the first half-split component and the screw surface of the second half-split component. For this reason, the pocket is accurately, simply and quickly formed with the screw surfaces of the first and second half-split parts exposed outside. The first half-split component and the second half-split component having the pocket formed therein are positioned and fixed integrally.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments.

FIG. 1 is a front view showing an embodiment of the hydrostatic screw of the present invention. As shown in FIG. 1, the first half-split part
Reference numeral 100 denotes a screw 1 that has penetrated, two pin holes 2 for positioning, which are arranged at the center in the axial direction and both sides in the radial direction of the screw 1, and a total of four pins 2 on both sides in the radial direction and both sides in the axial direction of the screw 1. It has a hole 3 for a tightening bolt and a mounting flange 4.
A seat 9 is formed around the hole 3 for the tightening bolt.
The first half-split part 100 is formed so that a nut member (not shown) is divided into two parts by a plane passing through its axis, and is paired with a second half-split part (not shown). The mounting flange 4 has mounting holes 5, 5 as shown in FIG.
As shown in FIGS. 3 and 4, the first half-split part has a pocket 6 formed by milling on the abdomen of the screw 1, that is, the screw surface 1a. These pockets 6 are trapezoidal depressions in cross section as shown in FIG. 4, and have a semicircular arc shape as shown in FIG. Also, the first half-split part
As shown in FIG. 3 and FIG. 4 which are cross sections taken along the line AA of FIG. 1, a conductive passage 7 connects the pressurized fluid supply hole 7 in the axial direction and the pocket 6 and the pressurized fluid supply hole 7. A hole 8 is provided as a fluid passage for the pressurized fluid. Similarly to the first half-split component 100, the second half-split component has a pocket, a pressurized fluid supply hole, a conduction hole, a tightening bolt hole, a seat, and a positioning pin hole. The first half-split part 100 and the second half-split part are positioned and overlapped by inserting positioning pins (not shown) into the pin holes 2, 2 and
Tightening bolts (not shown) are inserted through 3, 3, and 3 to integrally fix the first half-split component 100 and the second half-split component.

In the method of manufacturing the above-mentioned hydrostatic screw, a nut member is formed by cutting a screw on an inner peripheral portion of a cylinder using a cylindrical material (not shown) having a flange at one end. On the outer peripheral portion of the cylinder of the nut member, seats 9 and tightening bolt holes 3 are provided at four places on both sides in the radial direction and on both sides in the axial direction on each side (only one side is shown in FIG. 1). In addition, two positioning pin holes 2 shown in FIG. 1 are provided at the center of the nut member and on both sides in the radial direction. Further, a pressurized fluid supply hole 7 is provided in the axial direction as a fluid passage for the pressurized fluid. The flange 4 is provided with a mounting hole 5 shown in FIG. Then, the nut member is divided into two parts on a plane including the axis of the nut member, thereby producing a semi-finished product of the first half part 100 and the second half part (not shown). On the other hand, the thread surface 1a of the first half-split part 100 exposed to the outside is
As shown in FIGS. 4 and 5, the pocket 6 having a trapezoidal cross section is formed in a semicircular shape around the axis of the first half-split part 100. Further, the pocket 6 and the pressurized fluid supply hole 7
The conductive hole 8 is formed to conduct between the conductive material and the conductive material.

The first half part 100 and a pair of second half parts (not shown) are manufactured in exactly the same manner as described above.

The first half part 10 manufactured in this manner is
The position 0 and the second half-split portion are positioned by using a pin (not shown) in the positioning pin hole 2 and overlapped. Then, the tightening bolt is inserted into the hole 3 for the tightening bolt and tightened with a nut to integrally fix the first half-split part 100 and the second half-split part. Thus, the hydrostatic screw is completed.

In the hydrostatic screw having the above configuration, when the pressurized fluid is supplied to the pressurized fluid supply hole 7, the pressurized fluid flows into the pocket 6 via the conduction hole 7. The fluid in the pocket 6 supports a screw shaft (not shown) screwed to the screw 1 to a hydrostatic screw by static pressure.

In the above-described method for manufacturing a hydrostatic screw, the nut member is divided into two parts to form the first half-split part and the second half-split part, so that the screw surface existing on the inner surface of the nut member is exposed to the outside. . Therefore, the pocket 6 can be milled in a state where the screw surface 1a of the first half-split part is exposed to the outside,
The pockets 6 can be formed accurately, easily and quickly.
Also, the pocket of the second half-split part is exactly the same,
It can be formed accurately, easily and quickly.

In the above embodiment, the pocket is formed by milling. However, the pocket may be formed by a shaper, formed by plastic working such as embossing, or formed by etching.

In this embodiment, before the nut member is divided into the first half part 100 and the second half part,
Although the fluid supply hole 7 is processed, it may be processed after being divided into two. Further, the bolt hole 3, the seat 9, and the mounting hole 5 are machined before the nut member is divided into two parts, but may be machined after dividing the nut member into two parts.

[0018]

As is apparent from the above description, the hydrostatic screw according to the first aspect of the present invention has a first half-split part having a pocket formed on the thread surface and communicating with the fluid passage, and a fluid passage formed on the thread surface. Since the second half part having the pocket formed therein is formed in two parts, the pocket can be machined in a state where the thread surfaces of the first and second half parts are exposed to the outside. The pocket of the second half-split part can be formed accurately, easily and quickly.

According to a second aspect of the present invention, there is provided a method for manufacturing a hydrostatic screw.
The nut member having an internally threaded portion is divided into a first half-split component and a second half-split component on a plane, and the threaded surface inside the nut member is a screw of the first and second half-split components. Since the surface is exposed to the outside, the pocket can be formed accurately, easily, and quickly with the screw surfaces of the first and second half-split parts exposed to the outside.

[Brief description of the drawings]

FIG. 1 is a front view according to an embodiment of a hydrostatic screw of the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is an enlarged view of FIG. 3;

FIG. 5 is a sectional view of FIG. 3;

[Explanation of symbols]

1a: screw surface, 6: pocket, 7: pressurized fluid supply hole, 8: conduction hole, 100: first half cracked part.

Claims (2)

[Claims] A first half-split part having a threaded surface formed with a pocket leading to the fluid passage; a second half-split part having a threaded face formed with a pocket leading to the fluid passage; and the first half-split part And a fixing member for integrally fixing the second half-split part. 2. A nut member having a thread formed inside,
Dividing a plane into a first half-split part and a second half-split part; forming a pocket in the threaded surface of the first and second half-split parts; and the first half-split part and the second half-split part. Positioning the half-broken parts and fixing them together. A method for manufacturing a hydrostatic screw.