JPH0737703U - Flexible caster - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide a universal caster that can exhibit durability, rigidity, wear resistance and other superior functions by simply changing the shape of the mold parts. [Structure] The tire 5 is rotatably pivotally attached to the housing 1 and has a tire 5
Protrusions 6 are formed on the stay 4 that supports the tires to disperse the impact by hitting the housing when an impact load is applied to the tire. In addition, the stay shall be formed with an inclined surface so that it may be released from the mold after molding without losing its shape.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a caster, and more particularly to a strong and flexible caster that does not break or disassemble even when subjected to an impact load.

[0002]

[Prior art]

 As shown in FIGS. 7 and 12, the undercut inclined surface β was used to push open the molded product 50 (see FIGS. 9 and 10) and release the mold. Therefore, this conventional structure is expressed by a technical term called a structure without force.

The force-extracting structure is a method of using a shallow inclined surface, but since the force is generated as expressed as force-excluding, the shape of the undercut portion (see FIGS. 7B and 12) of the molded product is Collapse. That is, because the release plate 22 pushes the molded product 50 due to the mold release, it moves in the X ′ direction and opens in the Y ′ direction as shown in FIG. 10, so that the shape of the angle β collapses. Therefore, as described above, it becomes necessary to make the angle shallower and the inclination angle β smaller, and a solid and stable product cannot be obtained due to the assembly structure (Fig. 12). It lacks impact resistance and causes trouble in the market.

[0004]

[Problems to be solved by the device]

 An object of the present invention is to provide a caster capable of exhibiting superior functions such as durability and impact resistance as compared with the conventional ones by simply removing the drawbacks of the conventional structure and changing the shape of mold parts. .

[0005]

[Means for Solving the Problems]

 The means of the present invention are as follows.

(1) A stay supporting a tire is rotatably and pivotally mounted on a column provided in a housing, and when a load is applied to the tire, the stay is provided with a protrusion that disperses the impact by hitting the housing. caster.

(2) In a universal caster in which a stay supporting a tire is rotatably pivotally attached to a column provided in a housing, when the stay is molded and then removed from the injection molding die, the stay is pushed by pushing it with an ejection plate. A structure in which an inclined surface that expands and can be released without losing its shape is formed on the lower end surface of the stay.

(3) A deep shaft hole into which the tire support shaft is fitted is formed inside the stay, and the shaft hole is provided with a plane parallel to the hole center line on the entire circumference of the hole. The self-supporting caster described in item 2.

[0009]

【Example】

 A specific example of the universal caster according to the present invention will be described with reference to FIGS. 1 to 6.

Reference numeral 1 denotes a housing, which is suspended around a column 2, and a stage 4 having an insertion hole 3 into which the column 2 is inserted is assembled. The tire 5 is supported on the stay 4. In the present invention, the protrusion 6 is integrally provided on the upper end of the stay 4, and when the impact load is applied to the tire 5, the protrusion 6 of the stay 4 hits the housing 1 and is dispersed by the bent column 2 and the protrusion 6. Then, the tire 5 is structured to receive an excessive load. The shaft hole 12 inside the stay 4 for fixing the tire support shaft 11 that supports the tire 5 shown in FIG. 11 has a surface (α in FIGS. 2 and 11) parallel to the shaft center line over the entire circumference of the hole. Since it has, the support shaft 11 can be firmly held in the radial direction, and the looseness and play in the thrust direction can be absorbed. Further, an inclined surface 21 is formed on the lower end surface of the stay 4. By using the inclined surface 21 to push the ejection plate (22 in FIG. 4) like a wedge (FIGS. 4 to 6), it is possible to release the mold without breaking the shape of the deep rectangular undercut α. It is the one. A strong undercut structure has been made possible. Further, in the shaft hole 12 (FIG. 2) provided inside the stay 4, the surface α parallel to the hole center line is provided on the entire circumference of the hole as described above, and the mold can be released without breaking the shape. Therefore, the mounting position of the tire support shaft 11 assembled in the hole can be made wider and the supporting force can be strengthened.

[0011]

[Action]

 (Claim 1) Under normal load, the load applied to the tire 5 is supported by the stay 4, and the stay 4 is supported by the columns 2 provided in the housing 1. Although the flexibility is exhibited by the rotation of the stay 4 around the support column 2, sometimes an excessive load exceeding the design value, especially an impact load may be applied, causing damage and disassembly at that time.

According to the present invention, when an excessive impact load is applied, not only the bending moment applied to the supporting column 2 as in the conventional case but also the bending of the supporting column 2 and the protrusion 6 of the stay 4 contact the housing 1 and force is applied. The support part, the column 2, and the projection 6 that sandwich W are distributed and receive the force. Further, due to the recoil at the time of impact, a phenomenon occurs in which the tire 5 bounces with a strong force in the direction opposite to the force W, but the force can be received by the surface indicated by α.

(Claim 2) Since the contact surface between the ejection plate 22 and the forming stay 4 has an angle of γ, the movement as shown in FIGS. That is, when the push-out plate 22 pushes the stay 4 to separate the molded stay 4 from the mold, the force acts to open the inclined surface 21 of the molded stay 4 to the outside and does not move in the X direction of FIG. When it moves in the Y direction and the resistance of the α surface in FIG. 2 disappears, it moves in the X direction and is released from the mold to obtain the state of FIG.

(Claim 3) A deep shaft hole into which the tire support shaft is fitted is formed inside the stay, and the shaft hole has a surface parallel to the center line of the hole all around the hole. It can be released without breaking and can firmly support the tire support shaft in the radial direction. In addition, the elastic bending force of the stay that matches the releasing force can be secured, the looseness in the thrust direction, the play 40 (Fig. 11) can be absorbed, and the mounting position of the support shaft can be relaxed, so that the support force is also strong. .

[0015]

【effect】

 According to the present invention, it is possible to withstand a larger load and shock than the conventional casters and to be compact, and the economic effect is great in consideration of the material cost, the mounting operation, the storage space and the like.

[Submission date] January 11, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

(Claim 2) Since the contact surface between the ejection plate 22 and the forming stay 4 has an angle of γ, the movement as shown in FIGS. That is, when the push-out plate 22 pushes the stay 4 to separate the molded stay 4 from the mold, the force acts to open the inclined surface 21 of the molded stay 4 to the outside, and does not move in the X direction in FIG. It moves in the Y direction, and when there is no resistance on the α plane in FIG.

[Brief description of drawings]

FIG. 1 is an assembled sectional view.

FIG. 2 is a vertical sectional front view of a stay.

FIG. 3 is a vertical sectional side view of the above.

FIG. 4 is a sectional view before mold opening.

FIG. 5 is a cross-sectional view in the early stage of a mold release process.

FIG. 6 is a cross-sectional view showing a state before the end of the releasing step.

FIG. 7 is a vertical sectional front view of a conventional stay.

FIG. 8 is a vertical sectional side view of the above.

FIG. 9 is a cross-sectional view of a conventional product before mold opening.

FIG. 10 is a cross-sectional view showing an initial state of the releasing process in the above.

FIG. 11 is a cross-sectional view showing a state where a tire support shaft is assembled to the stay of the present invention.

FIG. 12 is a cross-sectional view in which a tire support shaft is attached to a conventional stay.

FIG. 13 is a cross-sectional view showing an example of changes in the shape and dimensions of the caster mounting portion.

FIG. 14 is a cross-sectional view showing an example of changes in the shape and dimensions of the caster mounting portion.

[Explanation of symbols]

 1 Housing 2 Support 3 Insertion Hole 4 Stay 5 Tire 6 Projection 11 Tire Support Shaft 12 Shaft Hole 21 Slope

Claims (3)

[Scope of utility model registration request] 1. A free caster in which a stay for supporting a tire is rotatably pivotally mounted on a column provided in a housing, and a projection is provided on the stay so as to disperse the impact by hitting the housing when an impact load is applied to the tire. . 2. In a universal caster in which a stay supporting a tire is rotatably pivotally mounted on a column provided in a housing, the stay expands when pushed out by an ejection plate when the stay is removed from the injection mold after molding. A structure in which an inclined surface that can be released without deforming is formed on the lower end surface of the stay. 3. A utility model registration claim in which a deep shaft hole into which the tire support shaft is fitted is formed inside the stay, and the shaft hole has a plane parallel to the center line of the hole all around the hole. Flexible caster as described in item.