JPH0336401Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a caster that is used by being attached to the lower part of a chair or other furniture or an audio rack.

In casters that are attached to furniture such as chairs or other objects, the shaft protruding from the wheel is inserted into the shaft hole provided in the shaft support, and the structure is such that the shaft is attached inseparably. It has already been implemented that the provided protrusion is engaged with an engagement groove provided in the circumferential direction on the outer periphery of the support shaft. When this shaft support is molded from synthetic resin, the protrusion molded on the inner circumferential surface of the shaft hole engages with the recess of the mold. Therefore, when separating the shaft support from the mold, the protrusion is forcibly separated from the recess of the mold, which requires time and effort, and the projection of the shaft hole is placed in the engagement groove of the support shaft. When the parts are engaged, a problem arises in that the height of the protrusion is lower than the required height, so that the protrusion is not sufficiently engaged with the engagement groove.

As a solution to this problem, JP-A-54-
The caster disclosed in Publication No. 126351 is formed by forming a pair of protrusions on the inner circumferential surface of the shaft hole at positions that do not overlap each other in the axial direction of the shaft hole, and intermittent in the circumferential direction. This is what I did. With this configuration, when molding the shaft support of the caster, the protrusions can be separated without causing distortion, but only one of the pair of protrusions is provided above or below the shaft hole in the vertical direction. Therefore, when a load is applied to a pair of wheels at the same time, only the support shaft of one wheel is supported by the protrusion and the engagement groove, and the support shaft of the other wheel cannot be said to be sufficiently supported. Also, when the wheels rotate, a load is applied to the side that moves in the horizontal direction, but even at this time, although the spindle of one wheel is supported, the spindle of the other wheel is not supported sufficiently, and rotation is slowed. There are problems that cannot be solved smoothly.

This invention prevents the locking protrusion provided on the inner circumferential surface of the shaft hole of the synthetic resin shaft support from deforming during mold release, reliably supports the wheel support shaft, and allows the rotation of the wheel. The purpose is to facilitate the

The caster of the present invention has a shaft hole formed in a shaft support body made of synthetic resin in a plate shape and placed in an upright position, and passed through the shaft support in the thickness direction. A pipe-shaped support shaft protruding from the side surface of the center part of the wheel is inserted from both sides with a space between the end surfaces of the support shaft, and a space is left in the inner peripheral surface of the shaft hole in the axial direction. A pair of locks provided at least at the upper and lower sides in the vertical direction and on both sides in the horizontal direction, each of which is intermittently provided at the same phase position with respect to the axis of the shaft hole. A rod-shaped pin is installed by engaging the protrusion with a groove provided in the circumferential direction of the outer periphery of the support shaft, and inserting both ends into the support shafts facing each other in the shaft hole, and the pair of wheels rotates. The shaft is freely supported, and an opening is opened toward the outside from half the circumference of the shaft hole between the pair of locking protrusions of the shaft support, and the opening is opened at a position that does not overlap with the shaft hole of the shaft support. It is characterized in that the upper part is made to protrude upward from the upper part and the mounting part is erected thereon.

The details of the caster of the present invention will be further explained based on the accompanying drawings. Reference numeral 1 denotes a shaft support body made of synthetic resin in the form of a plate and placed in an upright position, and a shaft hole 2 is provided through the shaft support 3 in the thickness direction of the shaft support 3 provided opposite to the center lower part of the shaft support body 1. . 4A and 4B in the diagram
In this method, a pair of notches are formed on the inner circumferential surface of the shaft hole 2 at intervals other than at least the upper and lower sides in the vertical direction and both sides in the horizontal direction, and each of the notches is intermittently cut out. These are locking protrusions provided at the same phase position with the axis of the shaft hole 2 as the center. Reference numeral 5 denotes a pair of synthetic resin wheels disposed on both sides of the shaft support 1, with a pipe-shaped support shaft 6 protruding from the side surface of the central portion thereof, and wheels 5 extending in the circumferential direction of the outer periphery of the tip of the support shaft 6. is a concave groove 7 that engages with the locking protrusions 4A and 4B of the shaft hole 2.
is provided. The support shafts 6, 6 of the pair of wheels 5, 5 are inserted into the shaft hole 2 of the shaft support body 1, and the shaft hole 2 is inserted into the shaft hole 2 of the shaft support body 1.
A pair of wheels 5, 5 are rotatably supported on both sides of the shaft support 1 by engaging the grooves 7 of the support shaft 6 with locking protrusions 4A, 4B provided on the inner peripheral surface of the shaft. ,
At this time, the length relationship between the shaft hole 2 and the support shaft 6 is determined so that a gap is provided between the tip surfaces of the support shafts 6, 6. Then, the support shafts 6, 6 facing each other in the shaft hole 2
A rod-shaped pin, shown as 8 in the figure, is installed with both ends inserted therein. Reference numeral 9 denotes a semi-cylindrical cover that covers the upper halves of the pair of wheels 5, 5 provided on the upper side of the shaft support 1, and this can be separate from the shaft support 1 or integrated. Good too. Reference numeral 10 denotes an opening opened outward from half the circumference of the shaft hole 2 between the pair of locking protrusions 4, 4 of the shaft support 1; They are almost the same, and in the one shown, the lower half of the shaft hole 2 is the opening.
Reference numeral 11 denotes a pipe-shaped attachment part for attaching this caster to the lower part of furniture, etc. via a bolt or shaft. It is installed by penetrating it.

The shaft support 1 is normally formed using a movable mold and a fixed mold that are separated on both sides of the shaft hole 2 in the axial direction. However, in such molding, the locking protrusions 4A and 4B are located at overlapping positions in the axial direction of the shaft hole 2, and molding on the inner side of the locking protrusions 4A and 4B is impossible with these molds. be. However, in what is shown here, the shaping of the shaft hole 2 between the locking protrusions 4A and 4B is carried out by moving the movable mold 12 shown by a dashed line in FIG. This is done by releasing the mold out of the shaft hole 2 through an opening 10 formed in the shaft hole 2, and the parts of the shaft hole 2 on both sides of the opening 10 are molded using a mold that can be punched out on both sides in the axial direction. That is,
This movable mold 12 has a prismatic shape, and its tip has a shaft hole 2.
Since it has a semi-cylindrical shape corresponding to the half circumference of the shaft hole 2, the thickness is the same as the inner diameter of the shaft hole 2, and the length is the same as that between the locking protrusions 4A and 4B, the molding can be performed in the axial direction of the shaft hole 2. If molding is carried out from the opening side of the shaft hole 2 to the locking protrusion 4 using a pair of molds, the locking protrusion 4 will not become an obstacle when separating the molds, and the desired locking protrusion 4 will be formed.
It becomes possible to mold A and 4B, and
The shaft hole 2 between the locking protrusions 4A and 4B can also be formed by the movable mold 12, and these molds can be easily separated.

Next, the assembly of the wheels 5 is similar to the known one,
Insert the support shaft 6 provided on this into the shaft hole 2 and push it in a little forcefully so that the groove 7 engages with the locking protrusions 4A and 4B, and then attach a rod-shaped pin to the tip of the support shaft 6. 8 and inserting the support shaft 6 of another wheel 5 from the opposite side of the rear shaft hole 2 in the same way, a pair of wheels 5, 5 are placed on both sides of the shaft support 1.
The wheels 5 are attached rotatably and inseparably, and the work can be done simply by forcefully pushing the support shaft 6 into the shaft hole 2, so the wheels 5 can be attached to the shaft support 1 efficiently and easily.

In the caster of the present invention, in the shaft support 1, between the pair of locking protrusions 4 in the shaft hole 2, half the circumference of the shaft hole 2 is formed as the opening 10, so that the locking protrusion 4 is connected to the shaft hole 2. They can be formed at the same phase position around the axis of . Therefore, since the pair of locking protrusions 4 can be set on the preferable vertical upper and lower sides of the circumferential direction of the circular shaft hole 2, as well as on both sides in the horizontal direction, the support shaft 6 of the wheel 5 can be reliably supported. be able to. Also, the shaft hole 2 rotatably supports the support shaft 6 of the wheel 5 without coming off.
The locking protrusions 4 on the inner circumferential surface are provided at least on the upper and lower sides in the vertical direction and on both sides in the horizontal direction, and in these parts they engage with the grooves 7 of the support shaft 6, so that the weight of furniture etc. to which the casters are attached is reduced. Even if a large load is applied, such as when the lower side of the pair of wheels 5 is wider than the upper side, or when the wheels 5 rotate to move furniture, etc., the horizontal direction of the pair of wheels 5 may be affected. The rotation of the wheels 5 is not inhibited because the distance on the moving side becomes wider than that on the opposite side. For this reason, there is less risk of wear and heat generation of the various constituent parts. Furthermore, since each of the pair of locking projections 4 is formed at the same phase position with respect to the axis of the shaft hole 2, the mold for molding the opening side of the locking projection 4 of the shaft hole 2 is symmetrical. It is only necessary to manufacture a pair of molds, which is extremely favorable in terms of mold manufacturing and management.

[Brief explanation of the drawing]

FIG. 1 is a bottom view of the caster of the present invention, FIG. 2 is a sectional view taken along the line AA in FIG. 1, and FIG. 3 is an exploded perspective view for explanation. 1... Pivotal supporting body, 2... Shaft hole, 3... Pivoting support, 4
... Locking protrusion, 5 ... Wheel, 6 ... Support shaft, 7 ... Concave groove, 10 ... Opening.

Claims (1)

[Scope of utility model registration request] From both sides of a shaft hole 2 formed by penetrating the shaft support 3 in the thickness direction of the shaft support 1, which is formed into a plate shape made of synthetic resin and placed in an upright position, at the lower center of the shaft support 3. A pipe-shaped support shaft 6 protruding from the side surface of the center portion of the wheel 5 is inserted with a gap between the tip surfaces of the support shaft 6, and is inserted into the inner peripheral surface of the shaft hole 2 with a gap in the axial direction. A pair of notches are formed at least on the upper and lower sides in the vertical direction and on both sides in the horizontal direction, and each of the notches is intermittently provided at the same phase position with respect to the axis of the shaft hole 2. A rod-shaped pin 8 is formed by engaging the stop protrusion 4 with a groove 7 provided in the circumferential direction of the outer periphery of the support shaft 6, and by inserting both ends into the support shafts 6, which face each other in the shaft hole 2.
is constructed, a pair of wheels 5, 5 are rotatably supported, and an opening is formed between the pair of locking protrusions 4, 4 of the shaft support 1 toward the outside from half the circumference of the shaft hole 2. 10
is opened, and furthermore, a mounting part 11 is erected at a position that does not overlap with the shaft hole 2 of the shaft supporting body 1 with its upper part protruding upward from the shaft hole 2.