JP3158600U - Caster frame and caster equipped with it - Google Patents

Abstract

The present invention provides a caster frame that is less likely to be charged with static electricity, even a non-conductive caster frame, and a caster including the caster frame. An inner surface 11A is formed so as to straddle a wheel 20, and a non-conductive frame main body 11 supporting a shaft portion 22 of the wheel 20 and a position offset from the shaft portion 22 of the wheel 20 of the frame main body 11. A conductive mounting shaft member 12 that is mounted so as to be exposed on the inner surface 11A, and is electrically conductive between the periphery of the exposed portion 12A of the mounting shaft member 12 and the region adjacent to the wheel on the inner surface of the frame body 11. A film 13 is provided. The conductive film 13 is formed by applying a metal powder, a metal piece, or a combination thereof in the paint. [Selection] Figure 1

Description

  The present invention relates to a caster frame and a caster including the caster frame, which are attached to various moving objects such as a shopping cart and a carrier bag.

  The caster is attached to an object to be moved, such as a shopping card body or a carrier bag, to facilitate the movement thereof. A caster generally includes a wheel that rolls on a floor surface, a caster frame that supports the wheel, and an attachment shaft member that is attached to an object to be moved.

  When the mounting shaft member is attached to the caster frame via a bearing to form a caster, and the caster mounting shaft member is attached to, for example, the leg of the shopping cart body, the caster frame is Since the shopping cart main body swings in the direction opposite to the traveling direction, the shopping cart main body can be moved while facing the free direction.

  The wheel is generally composed of a wheel having a through hole for inserting a shaft member, and an outer peripheral portion having elasticity such as rubber on the outer periphery of the wheel. In recent years, tire members that are formed using a conductive elastic member in which a conductive material such as carbon black, metal powder, or metal fiber is used alone or in combination have been put to practical use as a tire member as an outer peripheral portion ( For example, Patent Document 1).

  On the other hand, caster frames have been produced by molding a steel material such as stainless steel. In recent years, non-conductive materials such as plastics have been molded for weight reduction.

JP 2006-219022 A

  By the way, since the wheel rotates relative to the caster frame, static electricity may accumulate in the wheel and the caster frame. If both the caster frame and the wheel tire member are conductive, static electricity will not continue to accumulate in the caster frame if a discharge occurs between them, for example in the shopping cart itself. It is possible to avoid the accumulation of static electricity.

  However, if the caster frame is made of plastic for weight reduction as described above, static electricity continues to accumulate in the caster frame, static electricity accumulates in the shopping cart itself, and when the shopping cart user touches the operation handle, Discharge occurs between the hand of the shopping cart user and the operation handle.

  In view of the above, an object of the present invention is to provide a caster frame that is less likely to be charged with static electricity, even a non-conductive caster frame, and a caster including the same.

  In order to achieve the above object, the present invention has an inner surface extending over a wheel, and a non-conductive frame body that supports the wheel shaft, and a position offset from the wheel shaft. A conductive mounting shaft member attached to be exposed on the inner surface, and a conductive film provided between an area around the exposed portion of the mounting shaft member and a region close to the wheel on the inner surface of the frame body. Prepare.

  According to the present invention, since the conductive film is provided between the periphery of the exposed portion of the mounting shaft member and the area close to the wheel on the inner surface of the frame main body, the static electricity charged on the mounting shaft member is conducted. It is possible to escape to at least the conductive outer periphery of the wheel through the conductive film. Therefore, even if conductive wheels are attached to the caster frame and attached to various objects to be moved, static electricity is not easily generated.

It is a partially broken side view of the caster concerning a 1st embodiment of the present invention. (A) is the partially broken front view of the frame for casters shown in FIG. 1, (B) is sectional drawing of a wheel. It is a bottom view of the frame for casters shown in FIG.1 and FIG.2. It is a bottom view which shows the modification of the frame for casters shown in FIG. FIG. 4A is a partial cross-sectional view of a caster, and FIG. 5B is a bottom view of a caster frame according to a second embodiment of the present invention. It is a partially broken side view which shows the frame for casters which concerns on 3rd Embodiment of this invention. It is a partially broken sectional view which shows the frame for casters concerning 4th Embodiment of this invention. It is a partially broken side view which shows the caster which concerns on 5th Embodiment of this invention. It is a bottom view of the frame for casters shown in FIG.

  Hereinafter, some embodiments of the present invention will be described in detail with reference to the drawings.

  1 is a partially broken side view of a caster according to a first embodiment of the present invention, FIG. 2 (A) is a partially broken front view of a caster frame shown in FIG. 1, and (B) is a sectional view of a wheel. It is. As shown in FIGS. 1 and 2, the caster 1 includes a caster frame 10 and wheels 20.

  The caster frame 10 includes a frame main body 11, a mounting shaft member 12, and a conductive film 13.

  The frame body 11 has an inner surface 11 </ b> A formed so as to straddle the wheel 20, and supports the shaft portion 21 of the wheel 20. Since the frame body 11 is integrally formed of synthetic resin, it has non-conductivity.

  The mounting shaft member 12 is mounted with its axis directed up and down so as to be exposed to the inner surface 11A of the frame body 11 at a position offset from the shaft portion 21 of the wheel 20, that is, at a position displaced from the shaft portion 21. Since this mounting shaft member 12 is formed of steel, it has conductivity.

  The conductive film 13 is adjacent to the wheel 20 around the portion 12A where the mounting shaft member 12 is exposed on the inner surface of the frame body 11 (hereinafter referred to as an exposed portion) and the inner surface 11A of the frame body 11. Between the two regions. The conductive film 13 is made of a coating material in which either metal powder or metal piece or a combination thereof is mixed. As the metal powder or metal piece, for example, a metal material such as zinc or nickel can be used. Since the conductive film 13 is formed on the inner surface of the frame main body 11 by spraying or brushing, the conductive film 13 may be retrofitted to the ready-made frame main body 11.

  Since the frame main body 11 is made of a non-conductive material such as plastic, static electricity can be accumulated in the frame main body 11 and the mounting shaft member 12 by the rotation of the wheel 20. According to the present invention, the conductive film 13 is provided between the periphery of the exposed portion 12 </ b> A of the mounting shaft portion 12 and the region of the inner surface of the frame body 11 that is close to the wheel 20. If the caster frame 10 is equipped with the wheel 20 having the conductive outer peripheral portion 22, electric discharge is generated between the conductive film 13 and the outer peripheral portion 22, and the frame main body 11 and the mounting shaft member 12 are charged respectively. Can be prevented.

  Hereinafter, the first embodiment of the present invention will be described in detail. As shown in FIG. 1, the frame main body 11 is integrated with a flange portion 15 to which the shaft portion 21 of the wheel 20 is attached across the wheel 20 from above and a receiving portion 16 that rotatably supports the attachment shaft member 12. Molded.

  Specifically, the flange portion 15 includes a pair of side wall portions 15A and 15B that support the shaft portion 21 of the wheel 20, an upper wall portion 15C that connects the upper ends of the pair of side wall portions 15A and 15B, and a pair of side wall portions. It is comprised by 15 A and the front wall part 15D which connects both on the front side of 15B. The receiving portion 16 is connected to the pair of side wall portions 15A and 15B from above on the frame main body 11 between the upper wall portion 15C and the front wall portion 15D. That is, the bottom portion 16 </ b> A of the receiving portion 16 projects downward from the inner surface of the flange portion 15. Therefore, the inner surface 11A of the frame main body 11 is composed of the inner surfaces of the pair of side wall portions 15A and 15B, the upper wall portion 15C and the front wall portion 15D, and the bottom portion 16A of the receiving portion 16.

  The pair of side wall portions 15A, 15B is provided with a shaft hole for inserting the shaft portion 21 at the lower end thereof, and each side wall portion 15A, 15B has a front upper side and a rear upper side from the edge portion 15E of the shaft hole. And have a substantially fan shape extending in a slanted manner. The upper wall portion 15 </ b> C has a substantially semicircular cross section, and has a shape that can face the outer peripheral portion 22 of the wheel 20 on the outside thereof.

  The mounting shaft member 12 includes a main body portion 12B fitted from above and a cap portion 12C fitted into the main body portion 12B from below. The main body 12B is inserted into the mounting hole of the object 2 to be moved from below, and the main body 12B is fixed by the fixture 3.

  A radial bearing member 17 is provided between the receiving portion 16 and the mounting shaft member 12. Of the radial bearing member 17, the mounting shaft member 12 has an inner ring 17A attached to the outer peripheral surface of the body portion 12B of the mounting shaft member, an outer ring 17B attached to the mounting hole surface of the receiving portion 16, and an inner ring 17A and an outer ring. A bearing 17C is provided in a circumferential shape with a gap between the bearing 17C and 17B. As shown in the figure, a decorative annular plate 18 may be mounted between the upper and lower portions of the mounting shaft member 12 and the radial bearing member 17.

  In the frame main body 11 shown in FIGS. 1 and 2A, a bottom portion 16A of the receiving portion 16 is provided so as to protrude as a part of the inner surface, and the bottom portion 16A protrudes from the upper wall portion 15C side. . Therefore, in the vicinity of the bottom portion 16A, the distance between the outer peripheral portion 22 of the wheel 20 and the frame body 11 is short.

  FIG. 3 is a bottom view of the caster frame shown in FIGS. 1 and 2A. The conductive film 13 is provided on the bottom portion 16 </ b> A of the receiving portion 16. The distance between the conductive film 13 and the outer peripheral portion 22 of the wheel 20 is the shortest by providing it in the region connected to the upper wall portion 15C, as shown in FIG. 3, instead of providing the entire bottom portion 16A of the receiving portion 16. It becomes easy to discharge.

  Here, for the wheel 20, as shown in FIG. 2B, for example, a conductive tire as the outer peripheral portion 22 is provided on the outer periphery of the wheel 23 having a hole for passing the axle as the shaft portion 21. It only has to be done. The wheel 23 includes a wheel main body 23A provided with tires on the outer periphery, a pair of decorative plates 23B and 23C that are fitted into the hollow of the wheel main body 23A from the left and right, a mounting shaft portion of the pair of decorative plates 23B and 23C, and the wheel main body 23A. And a bearing 23D provided between the two shaft portions.

  According to this embodiment, even if the frame body 11 is non-conductive, the bottom portion 16A of the receiving portion 16 of the inner surface 11A of the frame body 11 protrudes from the inner surface of the flange portion 15 and the bottom portion 16A is the wheel 20. The distance from the outer peripheral portion 22 is shortened. Moreover, since the conductive film 13 is provided on the bottom portion 16 </ b> A, static electricity that can accumulate in the mounting shaft portion 12 can be discharged to the outer peripheral portion 22 of the conductive wheel 20. Therefore, it is possible to efficiently prevent the caster 1 from being charged with static electricity.

  In the first embodiment of the present invention, the conductive film 13 may also be provided on the exposed portion 12A of the mounting shaft member 12, and other regions of the inner surface 11A of the frame body 11, for example, as shown in FIG. Thus, it goes without saying that a part of the upper wall portion 15C of the collar portion 15 may be overhanged.

  In the first embodiment, since the receiving portion 16 protrudes below the upper wall portion 15C, it is sufficient to provide the conductive film 11 on the receiving portion 16, but the receiving portion 16 does not necessarily protrude. Even if it is a case, the same effect can be acquired even if the electroconductive film is provided along the upper wall part 15C from the lower part of the receiving part 16. FIG.

  5A and 5B relate to a second embodiment of the present invention, in which FIG. 5A is a partial cross-sectional view of a caster, and FIG. 5B is a bottom view of a caster frame. Members that are the same as or correspond to those shown in FIGS. 1 to 2A and 2B are assigned the same reference numerals, and descriptions thereof are omitted.

  In the frame main body 31, as shown in FIG. 5A, the receiving portion 36 is not exposed from the upper wall portion 35C. Even in that case, the conductive film is formed between the bottom portion 36A of the receiving portion 36 and the upper wall portion 35C, that is, up to the region where the distance from the outer peripheral portion 22 of the wheel 20 becomes narrower on the inner surface of the frame body 31. 33 is provided. For example, as shown in FIGS. 5A and 5B, the conductive film 33 may be provided up to the upper end of the upper wall portion 35 </ b> C, that is, vertically above the shaft portion 21 of the wheel 20.

  FIG. 6 is a partially cutaway side view showing a caster frame according to a third embodiment of the present invention. Members that are the same as or correspond to those shown in FIGS. 1 to 3 are given the same reference numerals, and descriptions thereof are omitted.

  As shown in FIG. 6, the conductive film 43 is an inner surface of at least one side wall portion 15 </ b> B of the inner surface 11 </ b> A of the frame main body 11, a region facing the side surface of the outer peripheral portion 22 of the wheel 20, and the receiving portion 16. It may be provided between the bottom 16A. For example, as shown in FIG. 6, the side wall portion 15 </ b> B may be provided so as to extend in the radial direction from the shaft portion 21. In this case, in the conductive film 43, the portion 43 </ b> B facing the side surface of the outer peripheral portion 22 of the wheel 20 on the side wall portion 15 </ b> B rather than the portion 43 </ b> A provided on the lower side of the receiving portion 16. 20 and the outer peripheral part 22 generate | occur | produce.

  FIG. 7 is a partially broken sectional view showing a caster frame according to a fourth embodiment of the present invention. Members that are the same as or correspond to those shown in FIGS. 1 to 3 are given the same reference numerals, and descriptions thereof are omitted.

  As shown in FIG. 7, the conductive film 53 is provided on the front wall portion 15 </ b> D of the mounting shaft member 12 on the inner surface of the frame body 11. In this case, the conductive film 53 generates a discharge between the lower end side of the front wall portion 15 </ b> D and the outer peripheral surface of the outer peripheral portion 22 of the wheel 20.

  FIG. 8 is a partially broken sectional view showing a caster according to a fifth embodiment of the present invention, and FIG. 9 is a bottom view of the caster frame shown in FIG. The fifth embodiment of the present invention shown in FIG. 8 differs from the caster frame shown in FIGS. 1 to 3 in the following points. That is, the bottom portion 16A of the receiving portion 16 of the caster frame 10 is that the bottom surface is not horizontal and protrudes downward to have a rib 16B. As shown in FIG. 9, a conductive film 13 is applied on the lower side of the rib 16B. Therefore, it becomes easy to discharge between the frame 10 for casters and the wheel 20. Note that the rib 16B has only to protrude downward, and for example, the shape of the truncated pyramid and the truncated cone and the cross section may be trapezoidal.

  Next, a confirmation experiment on the effect of the conductive film will be described. Two frame bodies 11 shown in FIGS. 1 to 3 were formed by mixing 15% by volume of glass fiber with 6-nylon. One frame body 11 was provided with a conductive film 13 as shown in FIGS. 1 to 3 by applying a coating containing 83 w% zinc powder. The conductive film 13 was not provided on the other frame body 11. One terminal of the power source of about 20,000 V was connected to the mounting shaft member 12 by wiring, the other terminal of the power source was connected to the probe, and the probe was brought close to the inner peripheral surface of the frame body. In the frame main body 11 provided with the conductive film 13, discharge was confirmed between the probe and the conductive film 13. On the other hand, no discharge occurred in the frame main body without the conductive film. Thereby, it is speculated that by providing the conductive film 13, static electricity charged in the mounting shaft member 12 can be discharged.

  Also, a wheel 20 having an outer peripheral portion 22 that is electrically conductive and a wheel having an outer peripheral portion that is not electrically conductive are prepared, a metal bar is passed across the two, and about 20,000 V is applied to the metal bar. Connected to one pole of the power supply. A probe was connected to the other pole of the power source, and the probe was brought close to the outer periphery of each wheel. Then, discharge was confirmed only when the probe was brought close to the wheel 20 whose outer peripheral portion 22 is conductive.

  As a result, even if it is a non-conductive frame main body, static electricity can be released from the mounting shaft portion by providing a conductive film around the mounting shaft portion, for example, the inner surface of the frame body including the receiving portion. It was found that the mounting shaft was not charged.

  Even if the present invention is a frame main body other than the shape of the embodiment shown in FIGS. 1 to 9, the inner surface of the frame main body is between the outer periphery of the exposed portion of the mounting shaft member and the region approaching the wheel. Of course, a conductive film may be provided, and it is needless to say that an area to be coated with the conductive film can be appropriately set according to the material of the frame body. That is, for example, as shown in FIG. 1, the conductive film 13 is applied not only to the bottom surface of the receiving portion 16 but also to the exposed portion 12 </ b> A as shown in FIG. 4 and the front wall portion 15 </ b> D as shown in FIG. 7. You may provide simultaneously. Furthermore, a conductive film may be provided on the inner surface of the frame body.

1: caster 2: object to be moved 3: fixture 10: caster frame 11: frame main body 11A: inner surface 12 of frame: mounting shaft member 12A: exposed portion 12B: main body portion 12C: cap portions 13, 33, 43 , 53: conductive film 15: flange portions 15A, 15B: side wall portions 15C, 35C: upper wall portion 15D: front wall portion 15E: edge 16 and 36 of shaft hole: receiving portions 16A and 36A: bottom portion 16B of receiving portion: Rib 17: Radial bearing member 17A: Inner ring 17B: Outer ring 17C: Bearing 18: Decorative annular plate 20: Wheel 21: Shaft portion 22: Outer peripheral portion 23: Wheel 23A: Wheel body 23B, 23C: Decorative plate 23D: Bearing

Claims (7)

An inner surface is formed so as to straddle the wheel, and a non-conductive frame main body that supports the shaft portion of the wheel;
A conductive mounting shaft member that is mounted to be exposed on the inner surface of the frame body at a position offset from the wheel shaft;
A conductive film provided between an area around the exposed portion of the mounting shaft member and an area close to the wheel on the inner surface of the frame body;
Caster frame with The frame main body is integrally formed with a flange portion on which a wheel shaft portion is attached across the wheel from above and a receiving portion that rotatably supports the attachment shaft member,
The inner surface of the frame body is formed by the inner surface of the flange portion and the bottom portion of the receiving portion that protrudes from the inner surface of the flange portion,
The caster frame according to claim 1, wherein the conductive film is provided on a bottom portion of the receiving portion.   The caster frame according to claim 2, wherein the conductive film is provided in a region of the bottom of the receiving portion that is connected to an upper wall portion of the flange that faces an outer peripheral portion of a wheel. The frame main body is integrally formed with a flange portion on which a wheel shaft portion is attached across the wheel from above and a receiving portion that rotatably supports the attachment shaft member,
The flange portion has a pair of side wall portions that support the shaft portion of the wheel,
The said electroconductive film was provided between the area | region facing the side surface of the outer peripheral part in the said wheel among the inner surfaces of at least one of said pair of side wall part, and the bottom part of the said receiving part. Frame for casters. The frame main body is integrally formed with a flange portion on which a wheel shaft portion is attached across the wheel from above and a receiving portion that rotatably supports the attachment shaft member,
The flange includes a pair of side wall portions that support the shaft portion of the wheel, and a front wall portion that is connected to the pair of side wall portions on the front side and surrounds the protruding portion of the receiving portion,
The caster frame according to claim 1, wherein the conductive film is provided on an inner surface of the front wall portion.   The caster frame according to any one of claims 1 to 5, wherein the conductive film is formed by mixing metal powder, metal pieces, or a combination thereof in a paint.   The caster comprised with the frame for casters in any one of Claims 1-6, and the wheel attached with respect to this frame for casters.

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