JPS62134237A - Screw shaft connecting mechanism for injection molding machine - Google Patents

Abstract

PURPOSE:To offer a screw shaft connecting mechanism to be easily mounted and dismounted and to simplify the procedures for mounting, dismounting and replacing of the screw shaft by forming a square pillar following the fitting section on part of the screw shaft and fixing the controlling component to prevent the screw shaft from moving to the axis revolving and axial directions, abutting against each of the faces of square pillar, to the end face of the driving component. CONSTITUTION:The screw 1a is installed at the end of screw shaft 1, while at the other end the fitting section 1b to fit in the fitting hole 2a of driving component 2 and the pillar 1c of beveled square following the fitting section 1b are provided. Two controlling components 3, 3 having the butting faces 3a, 3a butting against each of the faces of pillar 1c are bolted firmly with the bolt 4 to the driving component 2, with the said buttings of the faces 3a, 3a against each of faces of the pillar 1c as they are, and the screw shaft 1 is fixed to the driving component 2 integrally. By the said process, the restricting components can easily be fixed to the driving components firmly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a coupling mechanism for fixing the screw of an injection molding machine to a drive member for rotating and axially moving the screw.

Conventional technology The screws used in indexing molding machines vary depending on the type of molding material and
Depending on whether it's powder or pellets, you'll need to replace the screw. Furthermore, if the screw is used for a long time, it will become necessary to replace it due to Wl rubbing or corrosion. Therefore, conventionally, the screw shaft of an injection molding machine is removably fixed to the drive shaft. Since it is necessary to transmit both rotation and axial movement to the screw, fixing the screw shaft and the drive shaft that drives the screw shaft must be complicated.On the other hand, it is difficult to easily replace the screw. In order to achieve this, it is desirable to simplify the coupling mechanism between the screw shaft and the drive shaft. Therefore, a method of easily fixing the screw by tightening it in the direction of rotation of the screw was proposed (Utility Application No. 59-120875), but when removing the screw, the screw became too tight and it was difficult to remove it. A method has also been proposed in which a plurality of four spherical parts are provided on the circular surface of the screw shaft, and the screw is connected to a driving member that drives the screw via a ball that fits into the spherical recess.
A patent application has already been filed.

Problems to be Solved by the Invention An object of the present invention is to improve the shortcomings of the prior art and to provide a screw shaft coupling mechanism that is easy to attach and detach when fixing a screw shaft and a drive member for the screw shaft.

Means for Solving the Problem A fitting hole is provided on the end face of the drive member to fit the screw shaft, and a fitting hole is provided at the other end of the screw shaft having a screw at its tip to fit into the fitting hole. A prismatic portion is formed on a part of the screw shaft following the fitting portion, and a regulating member is provided which abuts each surface of the prismatic portion and prevents rotation and axial movement of the screw shaft. The above problem was solved by attaching and detaching the drive member to the end face of the drive member.

When the driving member rotates during action metering and crosstalk, the regulating member fixed to the driving member also rotates, and since the regulating member is in contact with each surface of the prismatic portion of the screw shaft, the screw shaft cannot be rotated. The rotation of the drive member is transmitted to the screw shaft. In addition, when the driving member moves in the axial direction of the screw shaft and performs injection, the screw shaft is moved in the axial direction from the driving member by the other end surface of the screw shaft, the bottom surface of the fitting hole of the driving member, and the regulating member. movement is transmitted.

Furthermore, the force applied to the screw shaft due to the melting pressure of the resin during metering and crosstalk is transmitted via the other end surface of the screw shaft and the bottom surface of the fitting hole of the drive member. and,
When replacing the screw, the screw can be easily removed by removing the above-mentioned regulating member from the drive part I, and when installing a new screw, the other end of the screw shaft must be fitted into the fitting hole. , the regulating member can be easily fixed by fixing it to the driving member.

Embodiment FIG. 1 is a front view showing a coupling mechanism between a drive member and a screw shaft in one embodiment of the present invention, FIG. 2 is a perspective view of the end of the screw shaft in the same embodiment, and FIG. It is an AA sectional view in a figure.

A screw 1a is provided at the tip of the screw shaft 1, and the other end has a fitting portion 1b that fits into a fitting hole 2a of a drive member 2, which will be described later, and a chamfered portion following the fitting portion 1b. A square column portion 1C formed into a square column is provided. The drive member 2 is coupled with a rotation mechanism that rotates the drive member 2 and an index drive mechanism that moves the drive member 2 in the axial direction. The driving member 2 is rotatably fixed to the bushing plate but immovable in the axial direction, and the driving member 2 is rotated by a rotary driving means such as a spline connection.
The pusher 1p-plate is moved in the axial direction using a ball screw or the like, and this point is not related to the gist of the present invention and will therefore be omitted.

A fitting hole 2a into which the screw shaft 1 is fitted is provided in the end face of the drive member 2, and the screw shaft 1 is inserted into the fitting hole 2a.
The fitting portion 1b is fitted, and the end surface of the screw shaft 1 is in contact with the bottom surface 2b of the fitting hole 2a. Following the fitting portion between the fitting hole 2a and the fitting portion 1b of the screw shaft 1, the screw shaft 1 is provided with a rectangular prism portion 1C, which is in contact with each surface of the prism portion 1C. The two regulating members 3, 3' having abutting surfaces 3a, 3a' that come into contact with each other are brought into contact with the drive member 2, with the abutting surfaces 3a, 3a' abutting each surface of the prismatic portion 1C as shown in FIG. It is fixed with bolts 4.

As a result, the screw shaft 1 is integrally fixed to the drive member 2. That is, when the driving member 2 is rotated during metering and crosstalk, the regulating member 3.
3' also rotates, and the contact surfaces 3a, 3a of the regulating members 3, 3'
' presses and rotates each surface of the prismatic portion 1C of the screw shaft 1, thereby rotating the screw 1a. At this time, the screw 1a tries to retreat (rightward in FIG. 1) due to the pressure caused by the melting of the resin, but the pressure caused by the melting of the resin causes the end surface of the fitting portion 1b of the screw shaft 1 to is transmitted to the drive member 2, and when the back pressure exceeds the back pressure applied to the drive member 2, the screw 1
a will retreat. Furthermore, when the drive member 2 is moved forward (to the left in FIG. 1) during injection, the bottom surface 2b of the fitting hole 2a presses the end surface of the fitting portion 1b of the screw shaft 1, causing the knee 18 to move. It is moved forward and the molten resin is injected.

As described above, the screw shaft coupling mechanism of this embodiment is configured and operates, but when replacing the slurry 5 and shaft 1,
Simply remove the bolt 4 from the drive member 2 and remove the regulating member 3.3.
'If removed, the screw shaft 1 will fit into the fitting hole 2a of the drive member 2.
Next, the fitting part 1b of the new screw shaft 1 is fitted into the fitting hole 2a of the drive member 2, and the contact surfaces 3a, 3a' of the regulating member 3゜3' are connected to the square column of the screw shaft 1. The regulating member 3.3' is brought into contact with each surface of the portion 1C.
Replacing the screw shaft 1 is completed by simply fixing it to the drive member 2 with the bolt 4.

In the above embodiments, the prismatic portion of the screw shaft is a square prism, but it may be a hexagonal prism or a triangular prism. Further, the length of the prismatic portion may be equal to or greater than the thickness of the regulating member, or may be equal to the thickness of the regulating member.

Effects of the Invention As described above, the present invention allows the screw shaft to be integrally fixed to the drive member simply by removing or attaching the regulating member from the drive member, making it extremely easy to remove, attach, and replace the screw shaft. It can be done easily.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the present invention, FIG. 2 is a perspective view of a main part of a screw shaft in the same embodiment, and FIG. 3 is a cross-sectional view taken along line A-A in FIG. 1...Screw shaft, 1a...Screw, 1b.
...Fitting part, 1C...Prismatic part, 2...Drive member, 2
a...ω: Matching hole, 3, 3'... Regulating member, 3a, 3
a'...Abutting surface, 4...Pol 1-0

Claims (1)

[Claims] In a mechanism for coupling a screw shaft to a drive member in an injection molding machine, a fitting hole provided on an end face of the drive member and the other end of the screw shaft having a screw at its tip fit into the fitting hole. a fitting part, and a regulating member in which a prismatic part is formed in a part of the screw shaft following the fitting part, and comes into contact with each surface of the prismatic part to prevent rotation and axial movement of the screw shaft. A screw shaft coupling mechanism for an injection molding machine, characterized in that the screw shaft coupling mechanism is detachably fixed to the end face of the drive member.