JP2003118307A - Wheel device using caster and handcart - Google Patents

Abstract

PROBLEM TO BE SOLVED: To semi-automatically restrain a wheel from being directed to the lower side of an inclined surface on a road surface inclined left and right without causing a hindrance to a free revolving property of a caster on a horizontal road surface. SOLUTION: A cam 16 integrally revolving with a yoke 13 is fastened on the side of the caster 10, and a restraining body 17 to restrain revolution by making contact with it is axially supported on a mounting base 11 free to revolve. In the meantime, a fixed frame 21 and a fixed axle 22 are provided in the rear of the caster 10, and a second wheel 25 is supported with a slider 24 free to move left. and right on it. A moving frame 23 is fixed on the slider 24, and this moving frame and a revolving body 27 axially supported on the fixed frame 21 are engaged with each other by a pin 23p and a slot 27o. Thereafter, the restraining body 17 and the revolving body 27 are connected to each other by a connecting rod 50.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【発明の属する技術分野】本発明は、左右傾斜した路面
においてキャスターの車輪が斜面下側へ向かないよう半
自動的に抑制可能な車輪装置と、これを用いた手押し車
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wheel device capable of semi-automatically restraining wheels of a caster from facing downward on a slope on a road surface inclined left and right, and a handcart using the wheel device.

【０００２】[0002]

【従来の技術】運搬台車、乳母車及び車椅子などのキャ
スターを用いた手押し車においては、人がこれを左右傾
斜した路面で押し進める場合に、重力の作用によりキャ
スターの車輪が斜面下側へ向いて手押し車が横向きに流
れ出してしまうこと（これを「横流れ」と呼ぶ）を起こ
す危険性があり、防止対策が必要とされている。2. Description of the Related Art In a handcart using casters such as a carrier cart, a baby carriage, and a wheelchair, when a person pushes the cart on a road surface inclined left and right, the wheels of the caster are pushed by the action of gravity toward the lower side of the slope. There is a risk that the car will flow out sideways (this is called "lateral flow"), and preventive measures are required.

【０００３】従来、横流れを防ぐことのできるものとし
ては、操作レバーに連動してキャスターを左右に傾けら
れるよう傾動機構を設けることにより、斜面上側に傾け
れば車輪が斜面下側に向くことを抑制できるレバー操作
式のキャスター（例えば特開平１１−３６３号公報を参
照）や、外周に直線状短径部を有するカムを取付軸に固
定支持し、このカムを押圧するローラをヨーク側に設け
ることにより、車輪の向きが所定の旋回範囲内において
直進方向に案内されるカム案内式のキャスター（例えば
特開平５−２５４３０４号公報を参照）がある。Conventionally, as a device capable of preventing lateral flow, a tilting mechanism is provided so that the casters can be tilted to the left and right in conjunction with an operating lever so that if the wheels are tilted to the upper side of the slope, the wheels are directed to the lower side of the slope. A lever-operated caster that can be restrained (see, for example, Japanese Patent Laid-Open No. 11-363) or a cam having a linear short-diameter portion on its outer periphery is fixedly supported on a mounting shaft, and a roller for pressing this cam is provided on the yoke side. As a result, there is a cam guide type caster in which the direction of the wheels is guided in a straight traveling direction within a predetermined turning range (for example, see Japanese Patent Laid-Open No. 5-254304).

【０００４】[0004]

【発明が解決しようとする課題】しかしながら、レバー
操作式のキャスターにおいては、必要の度に旋回抑制と
その後の元に戻す煩わしい手動操作が必要となる。また
カム案内式のキャスターでは、車輪が前側を向いた状態
にあると常に直進に案内する作用が働くために、水平な
路面において向きを変えるときには逆に抵抗となり支障
を来してしまう。そこで本発明は、これらの問題点を同
時に解決するために、左右傾斜した路面においてキャス
ターの車輪が斜面下側に向かないよう半自動的に抑制さ
れ、しかも水平な路面で自在に方向転換が可能な車輪装
置と、さらにこの車輪装置を用いて特別な操作なしに横
流れを防止可能な手押し車を提供することを目的とす
る。However, in the lever-operated caster, it is necessary to suppress the turning and to perform the troublesome manual operation for returning the caster whenever necessary. Further, in the cam guide type caster, when the wheels are directed to the front side, there is always a function of guiding the wheels straight, so that when the direction is changed on a horizontal road surface, resistance is adversely generated, which causes trouble. Therefore, in order to solve these problems at the same time, the present invention semi-automatically suppresses the wheels of the caster from facing the lower side of the slope on the road surface that is inclined left and right, and can change the direction freely on a horizontal road surface. An object of the present invention is to provide a wheel device and a wheelbarrow that can prevent a lateral flow without using a special operation using the wheel device.

【０００５】[0005]

【課題を解決するための手段】上記目的を達成するため
に本発明においては、取付台の下側にヨークが旋回自在
に軸支され、該ヨークの旋回中心から後方へ偏心して車
輪が回転自在に軸支されたキャスターと、周面の途中に
時計回りで乗り上げとなる右上昇面と反時計回りで乗り
上げとなる左上昇面を有し、該ヨークの旋回中心周りに
固着されたカムと、該カムの各上昇面に当接するための
当接部を有して回動可能に該取付台に軸支され、この当
接により該ヨークの旋回を抑制する抑制体と、該キャス
ターと前後離れて車台側に固定枠と共に取り付けられる
固定車軸と、該固定車軸に左右移動可能に装着されたス
ライダと、該スライダに一体的に左右移動可能そして回
転自在に装着された第２車輪と、該抑制体に回動を与え
るために、該固定枠に軸支された回動体を主体として、
該第２車輪の左右移動に連動して回動するよう設けられ
た回動機構と、該第２車輪が右へ移動すると該右上昇面
に、左へ移動すると該左上昇面に該当接部が当接するよ
う、該回動体と該抑制体を連結して回動を伝える連結部
材と、該スライダから該抑制体に至る連動経路の途中に
組み込まれ、該第２車輪を左右中立位置に戻すよう付勢
するばねとの、以上により車輪装置を構成する。In order to achieve the above object, according to the present invention, a yoke is pivotally supported on the lower side of a mounting base, and a wheel is rotatable eccentrically rearward from the pivot center of the yoke. A caster that is pivotally supported on the shaft, and a cam that has a right rising surface that rides in a clockwise direction and a left rising surface that rides in a counterclockwise direction in the middle of the peripheral surface, and is fixed around the turning center of the yoke. A restraining body that has a contact portion for contacting each rising surface of the cam and is rotatably supported by the mounting base, and that suppresses the turning of the yoke by this contact, and is separated from the caster in the front-rear direction. A fixed axle mounted on the chassis side together with a fixed frame, a slider mounted on the fixed axle so as to be movable left and right, a second wheel integrally mounted on the slider so as to be movable left and right, and rotatably, and the restraint. The fixation to give the body rotation As mainly supported by the rotary body to,
A rotation mechanism provided so as to rotate in association with the lateral movement of the second wheel, and a contact portion corresponding to the right rising surface when the second wheel moves to the right and a left rising surface when moving to the left. So as to come into contact with each other, the connecting member that connects the rotating body and the suppressing body to transmit the rotation, and the connecting member that is incorporated in the middle of the interlocking path from the slider to the suppressing body to return the second wheel to the left-right neutral position. The wheel device is constituted by the above and the spring for urging.

【０００６】前記車輪装置は、前記スライダに一体的に
左右移動する移動枠が設けられ、該移動枠及び前記回動
体の何れか一方に凸部、他方に該凸部と左右係合する凹
部が設けられて前記回動機構が構成されたものとするこ
とができる。また、前記固定車軸に雄ねじ、前記スライ
ダに該雄ねじに螺合する雌ねじが設けられ、前記回動体
が、前記スライダと係合して回動可能に、前記固定車軸
に支持されて前記回動機構が構成されたものとすること
もできる。さらに、前記雄ねじがボールねじ軸であり、
筒状の保持器に保持された多数の鋼球を介して、前記雌
ねじが該ボールねじ軸に螺合して前記回動機構が構成さ
れたものとすることもできる。そして、車台の後部に取
っ手が設けられ、前記いずれか１つの構成の車輪装置が
車台の左右に一対に取り付けられたものとして、手押し
車を構成する。[0006] In the wheel device, a moving frame that integrally moves to the left and right is provided on the slider, and one of the moving frame and the rotating body has a convex portion, and the other has a concave portion that laterally engages the convex portion. The rotation mechanism may be provided and configured. Further, the fixed axle is provided with a male screw, the slider is provided with a female screw to be screwed into the male screw, and the rotating body is rotatably supported on the fixed axle and rotatably engaged with the slider. Can also be configured. Further, the male screw is a ball screw shaft,
The female screw may be screwed onto the ball screw shaft through a large number of steel balls held by a cylindrical holder to configure the rotating mechanism. A handcart is configured by providing a handle on the rear portion of the chassis and having the wheel device having any one of the above configurations attached to the left and right of the chassis in pairs.

【０００７】[0007]

【発明の実施の形態】以下に本発明の実施の形態を実施
例に基づき図面を参照して説明する。BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on examples with reference to the drawings.

【０００８】図１から図４は、本発明による車輪装置の
第１の実施例を示したものである。四隅に取付穴11ａを
設けた板状の取付台１１の中央下側に支持軸１２をカシ
メにより固定してあり、支持軸１２には、上側に旋回中
心となる円筒部13ａがあって下側後方に向けて叉状とし
たヨーク１３を、軸受けＢ13を介して装着し、支持軸１
２の下端部にナットＮ12を締め付けてヨーク１３を旋回
自在に支持してある。そしてヨーク１３の下後端部に軸
受けＢ15付きの車輪１５を車軸１４で支持することによ
り、キャスター１０を基本構成してある。1 to 4 show a first embodiment of a wheel device according to the present invention. A supporting shaft 12 is fixed by caulking to the lower center of a plate-shaped mounting base 11 having mounting holes 11a at four corners. The supporting shaft 12 has a cylindrical portion 13a serving as a turning center on the upper side and a lower side. A fork-shaped yoke 13 facing rearward is mounted via a bearing B13, and the support shaft 1
A nut N12 is fastened to the lower end of the yoke 2 to support the yoke 13 so that the yoke 13 can freely rotate. The caster 10 is basically constructed by supporting the wheel 15 with the bearing B15 at the lower rear end of the yoke 13 by the axle 14.

【０００９】ヨークの円筒部13ａの外周には、図１０に
示したリング状で外周面の左後部に右上昇面16ａ、右後
部に左上昇面16ｂを成形したカム１６を固着してある。
また取付台１１の後部下側には支軸Ｓ17をカシメにより
固定してある。支軸Ｓ17には左右の腕部17ｌ、17ｒの各
前側にカム１６に当接するための当接部17ａ、17ｂを成
形した抑制体１７を、回動可能にブシュＢ17を介して支
持してある。当接部17ａ、17ｂはカムの最大径面16ｃの
半径よりも僅かに外側に位置させてある。On the outer periphery of the cylindrical portion 13a of the yoke, there is fixed a ring-shaped cam 16 shown in FIG. 10 in which a right rising surface 16a is formed at the left rear portion of the outer peripheral surface and a left rising surface 16b is formed at the right rear portion.
A support shaft S17 is fixed by caulking to the lower rear side of the mounting base 11. The support shaft S17 is rotatably supported via bushes B17 by restraining bodies 17 formed with contact portions 17a, 17b for contacting the cam 16 on the front sides of the left and right arm portions 17l, 17r. . The contact portions 17a and 17b are located slightly outside the radius of the maximum diameter surface 16c of the cam.

【００１０】一方、キャスター１０から後方に離れて、
門形で上面四隅に取付穴21ａを設けた固定枠２１に、そ
の左右下端部を切り欠いて固定車軸２２を差し渡し、両
端にナットＮ22を締め付けて固定してある。固定車軸２
２には筒状で内周面が摺動面であるスライダ２４を左右
両端に隙間Ｍ１を取って装着してある。スライダ２４に
は軸受けＢ25付きの第２車輪２５を装着し、さらに第２
車輪２５を跨ぐ門形の移動枠２３をはめて両端をナット
Ｎ24で締め付けることにより、移動枠２３、スライダ２
４そして第２車輪２５が一体的に左右移動するようにし
てある（以下、この基本構成の車輪組体を「スライド輪
２０」と呼ぶ）。On the other hand, apart from the caster 10 rearward,
A fixed frame 21 having a gate shape and provided with mounting holes 21a at its four corners is cut out at its lower left and right ends to pass a fixed axle 22, and nuts N22 are tightened and fixed at both ends. Fixed axle 2
A slider 24 having a cylindrical inner peripheral surface and a sliding surface is mounted on the left and right sides 2 with gaps M1 between the left and right ends. A second wheel 25 with a bearing B25 is attached to the slider 24, and a second wheel 25
By fitting the gate-shaped moving frame 23 that straddles the wheel 25 and tightening both ends with the nuts N24, the moving frame 23 and the slider 2
4 and the second wheel 25 are integrally moved left and right (hereinafter, the wheel assembly of this basic configuration is referred to as "slide wheel 20").

【００１１】固定枠２１の上部後方寄りの下側には支軸
Ｓ27をカシメにより固定してあり、支軸Ｓ27には、下部
前側に前腕部27ｆと中央左側に左腕部27ｌをもつ回動体
２７を、回動可能にブシュＢ27を介して支持してある。
前腕部27ｆには縦長の長穴27ｏを設けてあり、長穴27ｏ
には、移動枠２３の上部にカシメて設けたピン23ｐを左
右に係合するよう貫通させてある。これら移動枠２３と
回動体２７により回動機構を構成してある。なおこの構
成とは逆に、長穴27ｏを移動枠２３に、そしてピン23ｐ
を回動体２７に設けてもよい。また、ピン23ｐと長穴27
ｏに代えて玉継手を用いてもよく、或いは、回動体２７
にピニオンを固着し、移動枠２３の上部にこのピニオン
に噛み合うようラックを設けて回動機構を構成してもよ
い。A supporting shaft S27 is fixed to the lower side of the upper rear side of the fixed frame 21 by crimping, and the supporting shaft S27 has a rotating body 27 having a forearm portion 27f on the lower front side and a left arm portion 27l on the center left side. Is rotatably supported via a bush B27.
The forearm 27f is provided with a vertically long slot 27o.
A pin 23p, which is crimped on the upper portion of the moving frame 23, is penetrated through so as to engage in the left and right. The moving frame 23 and the rotating body 27 constitute a rotating mechanism. Contrary to this configuration, the elongated hole 27o is provided on the moving frame 23, and the pin 23p is provided.
May be provided on the rotating body 27. Also, pin 23p and slot 27
A ball joint may be used instead of o, or the rotating body 27
Alternatively, the pinion may be fixedly attached to the movable frame 23, and a rack may be provided on the upper portion of the moving frame 23 so as to mesh with the pinion to form a rotating mechanism.

【００１２】抑制体１７と回動体２７とは、前者の左の
腕部17ｌと後者の左腕部27ｌに連結棒５０をピン17ｐ、
27ｐで軸支することにより連結してある。連結棒５０は
固定枠２１の上部前面21ｂに設けた横長の長穴21ｏに通
してあり、連結棒５０には圧縮ばね28Ｂ、28Ａを長穴21
ｏを挟んで前後に装着し、前側の圧縮ばね28Ｂの前端と
後側の圧縮ばね28Ａの後端はそれぞれ止め輪Ｃ50で受け
止めてある。以上により車輪装置１LRを構成してある。The restraining body 17 and the rotating body 27 are such that the connecting rod 50 is connected to the left arm portion 17l of the former and the left arm portion 27l of the latter by a pin 17p,
It is connected by pivoting at 27p. The connecting rod 50 is passed through a horizontally long slot 21o provided in the upper front surface 21b of the fixed frame 21, and the connecting rod 50 is provided with compression springs 28B and 28A.
The front end of the compression spring 28B on the front side and the rear end of the compression spring 28A on the rear side are received by retaining rings C50, respectively. The wheel device 1LR is configured as described above.

【００１３】図５、図６には車輪装置１LRを２組用い
て、キャスター１０が両前輪、スライド輪２０が両後輪
となるように、板状の車台３０の左右下側に一対に、そ
れぞれの取付穴11ａ、21ａにボルトを通して取り付け、
車台３０の後部上側には取っ手４０を同じくボルトで取
り付けて構成した手押し車０１を示している。なお、カ
ム１６の取付位相を１８０度ずらし、連結棒５０も逆回
転位相で連結すれば前後逆の車輪配置に構成することも
可能である。In FIGS. 5 and 6, two pairs of wheel devices 1LR are used to form a pair of left and right lower sides of a plate-shaped chassis 30 so that the caster 10 serves as both front wheels and the slide wheels 20 serve as both rear wheels. Insert bolts through the mounting holes 11a and 21a,
On the upper rear side of the chassis 30, there is shown a wheelbarrow 01 in which a handle 40 is also attached by a bolt. It should be noted that if the mounting phase of the cam 16 is shifted by 180 degrees and the connecting rod 50 is also connected in the reverse rotation phase, it is possible to configure the wheel arrangement in the front-rear direction.

【００１４】次に、この手押し車０１及び車輪装置１LR
の動作について合わせて説明する。まず手押し車０１を
左へ傾斜した路面で押し進める場合（図７、図８を参
照）、手押し車０１に働く重力のうちキャスター１０に
作用する斜面成分（矢印Ｇ１）により、車輪１５は左へ
向きを変え始めようとするが、同時に、手押し車０１を
押す人は普通の対処として、直進方向を維持しようと取
っ手４０に力を加える。従って、車輪１５が瞬時に向き
を変えてしまうことはない。Next, the wheelbarrow 01 and the wheel device 1LR
The operation of is also described. First, when pushing the pushcart 01 on the road surface inclined to the left (see FIGS. 7 and 8), the wheel 15 is turned to the left due to the slope component (arrow G1) acting on the caster 10 in the gravity acting on the pushcart 01. However, at the same time, the person who pushes the pushcart 01 applies force to the handle 40 to maintain the straight traveling direction, as a normal measure. Therefore, the wheels 15 do not instantly change directions.

【００１５】一方、手押し車０１に働く重力のうちスラ
イド輪２０に作用する斜面成分（矢印Ｇ２）により、接
地している第２車輪２５に対して固定車軸２２が、固定
枠２１及び車台３０後部と共に左へ隙間Ｍ１の量だけ引
き寄せられる。相対的に見れば第２車輪２５は固定車軸
２２に対して右へ移動し、同時にスライダ２４と移動枠
２３も右へ移動する。このときピン23ｐが長穴27ｏに係
合したまま右へ移動するので、回動体２７は時計回り
（右回り（以下同様））に回動する。On the other hand, due to the slope component (arrow G2) acting on the slide wheel 20 in the gravity acting on the pushcart 01, the fixed axle 22 is fixed to the second wheel 25 which is in contact with the ground, the fixed frame 21 and the rear part of the chassis 30. At the same time, it is pulled to the left by the amount of the gap M1. When viewed relatively, the second wheel 25 moves to the right with respect to the fixed axle 22, and at the same time, the slider 24 and the moving frame 23 also move to the right. At this time, the pin 23p moves to the right while engaging with the elongated hole 27o, so that the rotating body 27 rotates clockwise (clockwise (the same applies hereinafter)).

【００１６】回動体２７の右回りの回動により、連結棒
５０が圧縮ばね28Ａを圧縮しながら前方へ移動して抑制
体１７を同じく右回りに回動させる。この回動により当
接部17ａがカムの右上昇面16ａに当接する。この当接に
より、カム１６と一体であるヨーク１３は反時計回り
（左回り（以下同様））に旋回しようとしても、そのた
めには当接部17ａを最大径面16ｃに押し上げなければな
らないので、左回りの旋回は抑制される。つまり、重力
作用により車輪１５は左へ向くことを半自動的に抑制さ
れる。従って、押す人は当初普通に取っ手４０に力を加
える以外は特に操作することなく、手押し車０１の左へ
の横流れを防ぐことができる。By the clockwise rotation of the rotating body 27, the connecting rod 50 moves forward while compressing the compression spring 28A, and the restraining body 17 is also rotated clockwise. By this rotation, the contact portion 17a contacts the right rising surface 16a of the cam. Due to this abutment, even if the yoke 13 integrated with the cam 16 tries to turn counterclockwise (counterclockwise (the same applies hereinafter)), the abutting portion 17a must be pushed up to the maximum diameter surface 16c for that purpose. Counterclockwise turning is suppressed. That is, the wheel 15 is semi-automatically restrained from turning to the left by the action of gravity. Therefore, the pushing person can prevent the lateral flow of the handcart 01 to the left without performing any operation other than to normally apply a force to the handle 40 at first.

【００１７】そして、左右水平な路面に戻った場合に
は、第２車輪２５を相対的に右へ移動させる重力作用は
ないので、圧縮ばね28Ａの弾発力により連結棒５０は前
後中立の位置に戻され、同時に回動体２７と抑制体１７
が左回りに回動を戻して当接部17ａがカム１６から離
れ、第２車輪２５はスライダ２４及び移動枠２３と共に
元の左右中立な位置に戻される（図１）。これにより、
ヨーク１３は旋回に抑制を受けなくなり、車輪１５を自
在に方向転換させることができる。When returning to the horizontal road surface on the left and right, there is no gravitational action for moving the second wheel 25 relatively to the right, so that the connecting rod 50 is moved to the neutral position by the elastic force of the compression spring 28A. The rotating body 27 and the suppressing body 17 at the same time.
Rotates counterclockwise to separate the contact portion 17a from the cam 16, and the second wheel 25 is returned to the original left-right neutral position together with the slider 24 and the moving frame 23 (FIG. 1). This allows
The yoke 13 is not restrained from turning, and the wheels 15 can be turned freely.

【００１８】他方、手押し車０１を右に傾斜した路面で
押し進める場合は（図９を参照）、上記とは左右逆の同
様の動作により、車輪１５は右へ向くことを半自動的に
抑制され、手押し車０１の右への横流れを防ぐことがで
きる。そして左右水平な路面に戻った場合には、同様に
各部が元の状態（図１）に戻され、車輪１５を自在に方
向転換させることができる。On the other hand, when pushing the pushcart 01 on the road surface inclined to the right (see FIG. 9), the wheel 15 is restrained from turning to the right semi-automatically by the same operation as the opposite of the above. It is possible to prevent lateral movement of the handcart 01 to the right. Then, when returning to the road surface that is horizontal to the left and right, each part is returned to the original state (FIG. 1) in the same manner, and the wheels 15 can be freely turned.

【００１９】次に、図１１から図１４は本発明による車
輪装置の第２の実施例を示したものである。板状の取付
台６１には上側にねじ軸状の取付部61ａを、下側に下半
分が小径部62ａである支持軸６２を一体的に成形して設
けてある。小径部62ａには、前側が旋回中心となる円筒
部63ａで、後側が逆Ｔ字形で左右に中空軸状であるヨー
ク６３を、ブシュＢ63を介して装着し下端部にナットＮ
62を締め付けて、旋回自在に支持してある。ヨーク６３
には車軸６４を左右に貫通させ、その両端部にブシュＢ
65付きの車輪６５を支持してあり、これにより双輪型の
キャスター６０を基本構成している。Next, FIGS. 11 to 14 show a second embodiment of the wheel device according to the present invention. On the plate-shaped mounting base 61, a screw shaft-shaped mounting portion 61a is provided on the upper side, and a support shaft 62 whose lower half is a small diameter portion 62a is integrally formed on the lower side. On the small diameter portion 62a, a yoke 63 having a cylindrical portion 63a having a front side as a turning center, a rear side having an inverted T shape and a hollow shaft shape on the left and right is mounted via a bush B63, and a nut N is provided at a lower end portion.
62 is fastened and is supported so that it can rotate freely. York 63
Axle 64 penetrates to the left and right, and bush B is attached to both ends.
It supports wheels 65 with 65, which basically constitutes a twin-wheel caster 60.

【００２０】ヨークの円筒部63ａの外周には、図２０に
示した円筒型で上端周面の右部に右上昇面66ａ、左部に
左上昇面66ｂを成形したカム６６を固着してある。また
支持軸６２の前側には、右左両側が軸部である両軸67ｓ
を固着してあって、両軸67ｓには、下記抑制体６７の別
離部分である、後方に向く腕状の２つの当接部67ａ、67
ｂを、それぞれ独立して回動可能に支持してある。当接
部67ａ、67ｂはカムの最上位面66ｃよりも通常は高い位
置を保つよう、取付台６１の右左両側に吊り下げた引張
ばね68Ａ、68Ｂにより引き上げられている。また当接部
67ａ、67ｂは、支持軸６２の右左両側に設けた突起部67
ｄに当たって止まることにより、水平より上には引き上
げられないようにしてある。また、支持軸６２の後側に
は後方に向けて支軸Ｓ67を固着して設けてあり、支軸Ｓ
67には、当接部67ａ、67ｂを押し下げるために右左に腕
部67ｒ、67ｌを具備した抑制体６７を、回動可能にブシ
ュＢ67を介して支持してある。On the outer circumference of the cylindrical portion 63a of the yoke, there is fixedly attached a cam 66 having a cylindrical shape shown in FIG. 20 and having a right rising surface 66a formed on the right side of the upper end peripheral surface and a left rising surface 66b formed on the left side. . In addition, on the front side of the support shaft 62, both shafts 67s whose right and left sides are shaft parts
Is fixed to both shafts 67s, and two arm-shaped abutting portions 67a, 67 facing rearward, which are separate parts of the suppressing body 67 described below, are attached.
b are rotatably supported independently of each other. The contact portions 67a and 67b are pulled up by tension springs 68A and 68B suspended on the right and left sides of the mounting base 61 so that the contact portions 67a and 67b normally maintain a position higher than the uppermost surface 66c of the cam. Also contact part
67a and 67b are protrusions 67 provided on both right and left sides of the support shaft 62.
By hitting d and stopping, it cannot be pulled up above the horizontal. Further, a support shaft S67 is fixedly provided rearward on the rear side of the support shaft 62.
A restraint body 67 having arm portions 67r, 67l on the right and left sides for pushing down the contact portions 67a, 67b is rotatably supported on the 67 via a bush B67.

【００２１】一方、キャスター６０から後方に離れて、
基端側は半ねじ軸部72ａで、先端側は右ねじ複リードの
ボールねじ軸部72ｂとした固定車軸７２を設けて、半ね
じ軸部72ａの先端側寄りには剛性のブシュＢ77をはめ、
さらに断面逆Ｌ字形の固定枠７１を穴を開けてはめてあ
り、半ねじ軸部72ａを取付相手である車台８０に差し込
んでナットＮ72で締め付けることにより、固定車軸７２
と固定枠７１を一体的に車台８０に取り付けられるよう
にしてある。On the other hand, apart from the caster 60 rearward,
A fixed axle 72 is provided with a semi-threaded shaft portion 72a on the base end side and a ball screw shaft portion 72b with a right-handed screw lead on the tip end side. A rigid bush B77 is fitted to the tip end side of the semi-threaded shaft portion 72a. ,
Further, a fixed frame 71 having an inverted L-shaped cross section is fitted with a hole, and the half-screw shaft portion 72a is inserted into a chassis 80 which is a mounting partner and is tightened with a nut N72.
The fixed frame 71 can be integrally attached to the chassis 80.

【００２２】ボールねじ軸部72ｂには、基端側に鍔部74
ｃのある筒状で内周面にボールねじ用の雌ねじ74ｂを成
形したスライダ７４を、筒状の保持器７６を介し両端に
隙間Ｍ２を取って装着してある。保持器７６には螺旋状
に多数の穴を配して各穴に鋼球76ｂを保持し、これを両
端に隙間Ｍ３（Ｍ３はＭ２の１／２以上必要）を取って
介在させてある。スライダ７４には軸受けＢ75付きの第
２車輪７５を装着し、先端部にナットＮ74を締め付けて
第２車輪７５がスライダ７４と一体的に左右移動するよ
うに支持してある。そしてボールねじ軸部72ｂの先端部
には鍔Ｃ72を固定してある（以下、この基本構成の車輪
組体を「スライド輪７０」と呼ぶ）。The ball screw shaft portion 72b has a collar portion 74 on the base end side.
A slider 74 having a cylindrical shape having a cylindrical shape c and formed with a female screw 74b for a ball screw on its inner peripheral surface is mounted via a cylindrical retainer 76 with a gap M2 at both ends. A large number of holes are spirally arranged in the cage 76 to hold the steel balls 76b in the respective holes, and these are interposed at both ends with a gap M3 (M3 is required to be 1/2 or more of M2). A second wheel 75 with a bearing B75 is mounted on the slider 74, and a nut N74 is fastened to the tip end of the slider 74 to support the second wheel 75 so as to move laterally integrally with the slider 74. A flange C72 is fixed to the tip of the ball screw shaft 72b (hereinafter, the wheel assembly of this basic configuration is referred to as "slide wheel 70").

【００２３】固定車軸７２にはめたブシュＢ77には、リ
ング状で外周の前側と後側に突出部77ａ、77ｂ及び外周
の上側と下側に各１／４周の幅で陥没部77ｃを成形した
回動体７７を装着してある。そして、スライダ７４の基
端側端面の上側と下側には各１／４周の幅で、陥没部77
ｃに左右摺動しながら回転係合するための爪状部74ｄを
設けて常時係合させてあり、これにより回動機構を構成
してある。The bush B77 fitted to the fixed axle 72 is formed with ring-shaped protrusions 77a and 77b on the front and rear sides of the outer circumference and recessed portions 77c on the upper and lower sides of the outer circumference with a width of 1/4 each. The rotating body 77 is attached. The recessed portion 77 has a width of ¼ circumference on the upper side and the lower side of the base end side surface of the slider 74.
A claw-shaped portion 74d for slidingly engaging the left and right sides of the c is provided so that the c is always engaged, and thereby a rotating mechanism is configured.

【００２４】抑制体６７と回動体７７との連結には、取
付台６１と固定枠７１の双方にねじ込んだ中空ねじ５ｃ
に両端支持した外装チューブ５１、５２の中に通し、両
端に円柱片５ｄを溶着したワイヤー５Ａ、５Ｂを用いて
いる。ワイヤー５Ａの両端は抑制体の腕部67ｒと回動体
の突出部77ａに、ワイヤー５Ｂの両端は腕部67ｌと突出
部77ｂに、各々切欠き穴を設け円柱片５ｄをはめ込んで
連結してある。なお、ワイヤー５Ａ、５Ｂに代えて、複
数のリンク及びレバーをピンで連結したリンク機構を用
いることも可能である。以上で車輪装置２Ｒを構成す
る。To connect the restraining body 67 and the rotating body 77, the hollow screw 5c screwed into both the mounting base 61 and the fixed frame 71.
Wires 5A and 5B are used which are passed through the exterior tubes 51 and 52 supported at both ends thereof and have cylindrical pieces 5d welded at both ends. Both ends of the wire 5A are connected to the arm portion 67r of the restraining body and the protruding portion 77a of the rotating body, and both ends of the wire 5B are connected to the arm portion 67l and the protruding portion 77b, respectively, by forming notch holes and fitting the columnar piece 5d therein. . Note that, instead of the wires 5A and 5B, it is possible to use a link mechanism in which a plurality of links and levers are connected by pins. The wheel device 2R is configured as described above.

【００２５】図１５、図１６には、パイプ製の車台８０
の右側に車輪装置２Ｒを、左側には車輪装置２Ｒとはス
ライド輪７０を左右反対向き（但し、ボールねじ軸部72
ｂは右ねじ）に構成した車輪装置２Ｌを取り付け、車台
８０の後部上側に取っ手９０を設けて構成した手押し車
０２を示している。なお、この手押し車０２は、座席或
いはかご等を取り付けることにより各種の用途に応用可
能なものである。In FIGS. 15 and 16, a chassis 80 made of pipe is used.
The wheel device 2R on the right side and the slide wheel 70 on the left side in the opposite direction to the wheel device 2R (however, the ball screw shaft portion 72
(b is a right-handed screw) 2 is attached to the wheel device 2L, and a wheelbarrow 02 configured by providing a handle 90 on the rear upper side of the chassis 80 is shown. The handcart 02 can be applied to various purposes by attaching a seat, a car, or the like.

【００２６】次に手押し車０２及び車輪装置２Ｒ、２Ｌ
の動作について合わせて説明する。なお、車輪装置２Ｒ
と２Ｌの動作は互いに同様であり、また前実施例との重
複を避けて本実施例では要点について説明する。Next, the handcart 02 and the wheel devices 2R and 2L.
The operation of is also described. In addition, the wheel device 2R
And 2L are similar to each other, and the main points will be described in this embodiment while avoiding duplication with the previous embodiment.

【００２７】まず、手押し車０２を右に傾斜した路面で
押し進める場合（図１７、図１８を参照）、重力の斜面
成分（矢印Ｇ７）により第２車輪７５は、スライダ７４
と共に固定車軸７２に対して相対的に左へ隙間Ｍ２の量
だけ移動する。このときスライダ７４は、鋼球76ｂを介
してボールねじ軸部72ｂに案内されながら、右ねじの螺
旋運動をする（図１７では紙面手前へ進む左回りとな
る）。鋼球76ｂはボールねじ軸部72ｂに沿って転動し、
これに伴って保持器７６は螺旋運動しながらスライダ７
４の移動量の半分だけ左へ移動する。First, when the pushcart 02 is pushed forward on the road surface inclined to the right (see FIGS. 17 and 18), the second wheel 75 is moved to the slider 74 by the slope component of gravity (arrow G7).
At the same time, it moves to the left relative to the fixed axle 72 by the amount of the gap M2. At this time, the slider 74 makes a spiral movement of the right-hand screw while being guided by the ball-screw shaft portion 72b via the steel ball 76b (in FIG. 17, it becomes a counterclockwise direction that moves toward the front of the page). The steel ball 76b rolls along the ball screw shaft 72b,
Along with this, the cage 76 spirally moves and the slider 7
Move to the left by half the movement amount of 4.

【００２８】一方、爪状部74ｄが陥没部77ｃと係合して
いるので、スライダ７４の右ねじの螺旋運動によって回
動体７７は前下がりに回動する。この回動は、ワイヤー
５Ａを引張ってキャスター６０側の抑制体６７を左下が
りに回動させ、引張ばね68Ｂを引き伸ばしながら当接部
67ｂを押し下げてカムの左上昇面66ｂに当接させる。こ
の当接により、カム６６と一体的であるヨーク６３の右
回りの旋回が抑制されるので、車輪６５は右へ向くこと
が抑制される。これは車輪装置２Ｌ側においても同様
で、重力作用で車輪６５は右へ向くことが抑制される
（図１９を参照）。従って、押す人は当初普通に直進を
保つよう取っ手９０に力を加える以外は特に操作しなく
ても、手押し車０２の右への横流れを防ぐことができ
る。On the other hand, since the claw-shaped portion 74d is engaged with the depressed portion 77c, the rotary body 77 is rotated forward and downward by the spiral movement of the right screw of the slider 74. In this rotation, the wire 5A is pulled to rotate the restraining body 67 on the caster 60 side to the left, and the tension spring 68B is stretched to abut the contact portion.
67b is pushed down and brought into contact with the left rising surface 66b of the cam. By this abutment, the clockwise rotation of the yoke 63 that is integral with the cam 66 is suppressed, so that the wheels 65 are suppressed from turning to the right. This is the same on the wheel device 2L side, and the wheel 65 is prevented from turning to the right by the action of gravity (see FIG. 19). Therefore, the pusher can prevent the pushcart 02 from flowing laterally to the right without any particular operation other than applying a force to the handle 90 so that the pusher normally keeps going straight.

【００２９】そして左右水平な路面に戻った場合には、
引張ばね68Ｂが当接部67ｂを引き上げてカム６６から離
す。同時に、抑制体６７が左右水平に戻され、ワイヤー
５Ａが引張られて回動体７７を回動中立に戻し、そして
第２車輪７５がスライダ７４と共に左右中立の位置に戻
されて元どおりとなる（図１１）。これによりヨーク６
３は旋回に何の抵抗も受けなくなり、車輪６５を自在に
方向転換させることができる。他方、左に傾斜した路面
から戻る場合も左右逆で同様の動作である。Then, when returning to a horizontal road surface,
The tension spring 68B pulls up the contact portion 67b and separates it from the cam 66. At the same time, the restraining body 67 is returned horizontally to the left and right, the wire 5A is pulled to return the turning body 77 to the turning neutral position, and the second wheel 75 is returned to the left and right neutral position together with the slider 74 to restore the original state ( (Fig. 11). This makes the yoke 6
3 does not receive any resistance to turning, and the wheels 65 can be freely turned. On the other hand, when returning from a road surface inclined to the left, the same operation is performed with the right and left reversed.

【００３０】[0030]

【発明の効果】本発明は以上の説明のように構成されて
いるので、次のような効果を奏する。取付台に軸支した
抑制体がヨークに固着したカムに当接可能であるよう構
成したキャスターと、固定車軸にスライダを介して左右
移動可能に第２車輪を支持して構成したスライド輪を、
第２車輪の左右移動により抑制体が回動してカムに当接
するよう連結することにより、左右傾斜した路面におい
て重力作用でキャスターの車輪が斜面下側に向こうとし
ても、これを同じ重力作用で半自動的に抑制することが
でき、しかも水平な路面においては自由に方向転換させ
ることができる、このような特長を兼ね備えた従来にな
い車輪装置を得ることができる。Since the present invention is configured as described above, it has the following effects. A caster configured so that a restraint member axially supported by a mounting base can contact a cam fixed to a yoke; and a slide wheel configured to support a second wheel on a fixed axle so as to be movable left and right via a slider,
By connecting the second body to the cam so that the restraining body rotates and abuts on the cam due to the lateral movement of the second wheel, even if the wheels of the caster try to move to the lower side of the slope due to the gravity action on the road surface that is inclined left and right, the same gravity action is applied. It is possible to obtain an unprecedented wheel device that can be semi-automatically restrained and can freely change the direction on a horizontal road surface, having such features.

【００３１】また、スライダに移動枠を固着し、この移
動枠及び回動体の何れか一方に凸部と、他方にこの凸部
と左右係合する凹部を設けて抑制体を回動させるための
回動機構を構成することにより、門形の固定枠内の上部
空間に回動機構を組み込んでキャスターとスライド輪と
を同じ車輪サイズに、しかも同じ取付方法とすることが
できるので、運搬台車に最適な車輪装置を得ることがで
きる。Further, a moving frame is fixed to the slider, a convex portion is provided on one of the moving frame and the rotating body, and a concave portion which engages with the convex portion on the left and right is provided on the other side to rotate the suppressing body. By configuring the turning mechanism, the turning mechanism can be incorporated in the upper space of the gate-shaped fixed frame, and the caster and the slide wheel can have the same wheel size and the same mounting method. An optimum wheel device can be obtained.

【００３２】また、固定車軸に雄ねじ、スライダにはこ
の雄ねじに螺合する雌ねじを設け、そしてスライダに係
合して回動するよう回動体を固定車軸に支持して回動機
構を構成することにより、第２車輪のサイズに関係なく
コンパクトに回動機構を組むことができるので、乳母車
や車椅子などに適した車輪装置を得ることができる。Further, the fixed axle is provided with a male screw, the slider is provided with a female screw which is screwed to the male screw, and the rotating body is supported on the fixed axle so as to engage with the slider and rotate to form a rotating mechanism. Thus, the turning mechanism can be assembled compactly regardless of the size of the second wheel, so that a wheel device suitable for a baby carriage, a wheelchair, etc. can be obtained.

【００３３】また、固定車軸の雄ねじをボールねじ軸と
し、これに筒状の保持器に保持された鋼球を介してスラ
イダの雌ねじを螺合させることにより、スライダの左右
移動がスムーズになり、しかも鋼球循環式のボールねじ
に比べて構造が簡単である。Further, the male screw of the fixed axle is used as a ball screw shaft, and the female screw of the slider is screwed onto the ball screw shaft through a steel ball held by a cylindrical retainer, so that the slider can be moved laterally smoothly. Moreover, the structure is simpler than that of a steel ball circulation type ball screw.

【００３４】そして、この車輪装置を車台の左右に一対
に取り付け、車台の後部には取っ手を設けることによ
り、左右傾斜した路面において特に操作することなく横
流れを防ぐことのできる、より実用的な手押し車を得る
ことができる。By installing a pair of the wheel devices on the left and right sides of the chassis and providing a handle on the rear part of the chassis, a more practical hand push capable of preventing lateral flow without any operation on a road surface inclined left and right. You can get a car.

【図面の簡単な説明】[Brief description of drawings]

【図１】第１実施例の車輪装置の平面図（取付台及び固
定枠は透視）である。FIG. 1 is a plan view of a wheel device according to a first embodiment (a mount and a fixed frame are seen through).

【図２】第１実施例の車輪装置の左側面図（固定枠の左
側部は切断）である。FIG. 2 is a left side view of the wheel device according to the first embodiment (the left side portion of the fixed frame is cut).

【図３】第１実施例の車輪装置のキャスター断面図（図
２のＡ−Ａ断面）である。FIG. 3 is a caster cross-sectional view (cross section AA in FIG. 2) of the wheel device according to the first embodiment.

【図４】第１実施例の車輪装置のスライド輪断面図（図
２のＢ−Ｂ断面）である。FIG. 4 is a slide wheel cross-sectional view (cross-section taken along the line BB in FIG. 2) of the wheel device according to the first embodiment.

【図５】第１実施例の手押し車の平面図（車台は透視）
である。FIG. 5 is a plan view of the wheelbarrow of the first embodiment (the chassis is transparent).
Is.

【図６】第１実施例の手押し車の左側面図である。FIG. 6 is a left side view of the handcart of the first embodiment.

【図７】第１実施例の車輪装置の左傾斜路面での平面状
態図である。FIG. 7 is a plan view of the wheel device of the first embodiment on a left-inclined road surface.

【図８】第１実施例の車輪装置の左傾斜路面でのスライ
ド輪後面状態図である。FIG. 8 is a rear surface state view of a slide wheel on a left slope road surface of the wheel device according to the first embodiment.

【図９】第１実施例の車輪装置の右傾斜路面での平面状
態図である。FIG. 9 is a plan view showing a state of a right inclined road surface of the wheel device according to the first embodiment.

【図１０】第１実施例の車輪装置のカムの平面図であ
る。FIG. 10 is a plan view of a cam of the wheel device according to the first embodiment.

【図１１】第２実施例の車輪装置の平面図（取付台は透
視）である。FIG. 11 is a plan view of the wheel device according to the second embodiment (the mount is seen through).

【図１２】第２実施例の車輪装置の左側面図（左側の車
輪は除く）である。FIG. 12 is a left side view (excluding the left wheel) of the wheel device according to the second embodiment.

【図１３】第２実施例の車輪装置のキャスターを後方か
ら見た左半分断面図である。FIG. 13 is a left half sectional view of a caster of the wheel device according to the second embodiment as viewed from the rear.

【図１４】第２実施例の車輪装置のスライド輪を後方か
ら見た主要部断面図である。FIG. 14 is a sectional view of a main part of a slide wheel of a wheel device according to a second embodiment of the present invention, as viewed from the rear.

【図１５】第２実施例の手押し車の平面図である。FIG. 15 is a plan view of the wheelbarrow of the second embodiment.

【図１６】第２実施例の手押し車の左側面図である。FIG. 16 is a left side view of the handcart of the second embodiment.

【図１７】第２実施例の車輪装置（右側用）の右傾斜路
面での側面状態図である。FIG. 17 is a side view showing the state of the wheel device (for the right side) of the second embodiment on the right sloping road surface.

【図１８】第２実施例の車輪装置（右側用）の右傾斜路
面での後面状態図である。FIG. 18 is a rear surface state diagram of the wheel device (for the right side) of the second embodiment on the right sloping road surface.

【図１９】第２実施例の車輪装置（左側用）の右傾斜路
面での後面状態図である。FIG. 19 is a rear surface state diagram of the wheel device (for the left side) of the second embodiment on the right sloping road surface.

【図２０】第２実施例の車輪装置のカムの平面図（ａ）
及び左側面図（ｂ）ある。FIG. 20 is a plan view of the cam of the wheel device according to the second embodiment (a).
And a left side view (b).

【符号の説明】[Explanation of symbols]

１１、６１ 取付台 ２１、７１ 固定枠 １２、６２ 支持軸 ２２、７２ 固定車軸 １３、６３ ヨーク ２３ 移動枠 １４、６４ 車軸 ２４、７４ スライダ １５、６５ 車輪 ２５、７５ 第２車輪 １６、６６ カム ７６ 保持器 １７、６７ 抑制体 ２７、７７ 回動体 28Ａ、28Ｂ 圧縮ばね 68Ａ、68Ｂ 引張ばね ５０ 連結棒 ５Ａ、５Ｂ ワイヤー ３０、８０ 車台 ４０、９０ 取っ手 １０、６０ キャスター ２０、７０ スライド輪 １LR、２Ｌ、２Ｒ 車輪装置 ０１、０２ 手押し車 11, 61 Mounting base 21, 71 Fixed frame 12, 62 Support shaft 22, 72 Fixed axle 13, 63 Yoke 23 Moving frame 14,64 axles 24,74 sliders 15,65 wheels 25,75 second wheels 16, 66 Cam 76 Cage 17, 67 Suppressing body 27, 77 Rotating body 28A, 28B compression spring 68A, 68B tension spring 50 Connecting Rod 5A, 5B Wire 30, 80 Chassis 40, 90 Handle 10,60 casters 20,70 slide wheels 1LR, 2L, 2R Wheel device 01, 02 wheelbarrow

Claims (5)

【特許請求の範囲】[Claims] 【請求項１】 取付台の下側にヨークが旋回自在に軸支
され、該ヨークの旋回中心から後方へ偏心して車輪が回
転自在に軸支されたキャスターと、周面の途中に時計回
りで乗り上げとなる右上昇面と反時計回りで乗り上げと
なる左上昇面を有し、該ヨークの旋回中心周りに固着さ
れたカムと、該カムの各上昇面に当接するための当接部
を有して回動可能に該取付台に軸支され、この当接によ
り該ヨークの旋回を抑制する抑制体と、該キャスターと
前後離れて車台側に固定枠と共に取り付けられる固定車
軸と、該固定車軸に左右移動可能に装着されたスライダ
と、該スライダに一体的に左右移動可能そして回転自在
に装着された第２車輪と、該抑制体に回動を与えるため
に、該固定枠に軸支された回動体を主体として、該第２
車輪の左右移動に連動して回動するよう設けられた回動
機構と、該第２車輪が右へ移動すると該右上昇面に、左
へ移動すると該左上昇面に該当接部が当接するよう、該
回動体と該抑制体を連結して回動を伝える連結部材と、
該スライダから該抑制体に至る連動経路の途中に組み込
まれ、該第２車輪を左右中立位置に戻すよう付勢するば
ねとの、以上により構成される車輪装置。1. A caster in which a yoke is rotatably supported on the lower side of a mounting base, and a wheel is rotatably supported eccentrically rearward from the center of rotation of the yoke, and in a clockwise direction in the middle of the peripheral surface. It has a right rising surface that rides up and a left rising surface that rides counterclockwise, and has a cam fixed around the turning center of the yoke and a contact portion for contacting each rising surface of the cam. And pivotally supported by the mounting base so as to be pivotally supported by the abutment to suppress the turning of the yoke by this abutment, a fixed axle mounted on the chassis side with a fixed frame apart from the casters in the front-rear direction, and the fixed axle. To the slider, a second wheel integrally mounted on the slider so as to be movable left and right, and rotatably mounted on the slider, and pivotally supported by the fixed frame to impart rotation to the restraining body. The rotating body is the main
A rotation mechanism provided so as to rotate in association with the lateral movement of the wheel, and the contact portion abuts on the right rising surface when the second wheel moves to the right and the left rising surface when the second wheel moves to the left. So as to connect the rotating body and the suppressing body to transmit the rotation,
A wheel device constituted by the above, including a spring that is incorporated in the interlocking path from the slider to the restraining member and that urges the second wheel to return to the left-right neutral position. 【請求項２】 前記スライダに一体的に左右移動する移
動枠が設けられ、該移動枠及び前記回動体の何れか一方
に凸部、他方に該凸部と左右係合する凹部が設けられて
前記回動機構が構成された請求項１に記載の車輪装置。2. A slider is provided with a moving frame that moves to the left and right integrally with the slider, and one of the moving frame and the rotating body is provided with a convex portion, and the other is provided with a concave portion that engages with the convex portion left and right. The wheel device according to claim 1, wherein the rotating mechanism is configured. 【請求項３】 前記固定車軸に雄ねじ、前記スライダに
該雄ねじに螺合する雌ねじが設けられ、前記回動体が、
前記スライダと係合して回動可能に、前記固定車軸に支
持されて前記回動機構が構成された請求項１に記載の車
輪装置。3. The fixed axle is provided with a male screw, the slider is provided with a female screw screwed into the male screw, and the rotating body is provided with:
The wheel device according to claim 1, wherein the rotation mechanism is configured to be supported by the fixed axle so as to be rotatable by being engaged with the slider. 【請求項４】 前記雄ねじがボールねじ軸であり、筒状
の保持器に保持された多数の鋼球を介して、前記雌ねじ
が該ボールねじ軸に螺合するものである請求項３に記載
の車輪装置。4. The male screw is a ball screw shaft, and the female screw is screwed onto the ball screw shaft through a large number of steel balls held by a cylindrical cage. Wheel device. 【請求項５】 車台の後部に取っ手が設けられ、請求項
１から４のいずれか１項に記載の車輪装置が車台の左右
に一対に取り付けられた手押し車。5. A wheelbarrow in which a handle is provided on the rear part of the chassis, and the wheel device according to claim 1 is mounted on the left and right of the chassis in pairs.