JPS59170554A - Belt type stepless transmission device - Google Patents

Belt type stepless transmission device

Info

Publication number
JPS59170554A
JPS59170554A JP4643283A JP4643283A JPS59170554A JP S59170554 A JPS59170554 A JP S59170554A JP 4643283 A JP4643283 A JP 4643283A JP 4643283 A JP4643283 A JP 4643283A JP S59170554 A JPS59170554 A JP S59170554A
Authority
JP
Japan
Prior art keywords
rotating body
output shaft
sleeve
spring
belt
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP4643283A
Other languages
Japanese (ja)
Inventor
Yasuo Uchikawa
靖夫 内川
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kubota Corp
Original Assignee
Kubota Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kubota Corp filed Critical Kubota Corp
Priority to JP4643283A priority Critical patent/JPS59170554A/en
Publication of JPS59170554A publication Critical patent/JPS59170554A/en
Pending legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16H—GEARING
    • F16H9/00—Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by endless flexible members
    • F16H9/02—Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by endless flexible members without members having orbital motion
    • F16H9/04—Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by endless flexible members without members having orbital motion using belts, V-belts, or ropes
    • F16H9/12—Gearings for conveying rotary motion with variable gear ratio, or for reversing rotary motion, by endless flexible members without members having orbital motion using belts, V-belts, or ropes engaging a pulley built-up out of relatively axially-adjustable parts in which the belt engages the opposite flanges of the pulley directly without interposed belt-supporting members

Abstract

PURPOSE:To contrive to prevent the slippage of a transmission belt from occurring by a structure wherein cam mechanisms to increase the force of a spring with the increase of the difference between the rotational speed of an output shaft and that of one rotating body is provided in a transmission device, in which the one rotating body of an output split pulley is energized through a sleeve in the direction toward the other rotating body by the spring. CONSTITUTION:A belt type stepless transmission device consists in winding a transmission belt 12 across an input split pulley 9 attached to an input shaft 8 connected to an engine 6 (not shown) and an output split pulley 11 attached to an output shaft 10 connected to an transmission gear. In this case, the first rotating body 11a of the output split pulley 11 is fitted onto a sleeve 13, which is splinedly fitted onto the output shaft 10 and at the same time energized through a pair of pins 14 attached on said rotating body 11a in the direction toward a second rotating body 11b by means of a spring 15. In addition, notches 13a are provided at the parts, in which the pins 14 of the sleeve 13 are inserted, so as to form cam surfaces 20 on the parts of the inner wall surfaces of the notches 13a in order to realize cam mechanisms 22 by annexing rollers 21, each of which contacts against the cam surface 20, to the pins 14.

Description

【発明の詳細な説明】 本発明は、出力側ブーＩＪ　において第１回転体を第２
回転体に接近するようにスプリングによシ摺動付勢する
と共に、前記第１回転体を出力軸に相対回転自在に取付
けたベルト式無段変速装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention provides a first rotating body in an output side boolean IJ.
The present invention relates to a belt-type continuously variable transmission in which the first rotating body is slidably biased by a spring so as to approach a rotating body, and the first rotating body is relatively rotatably attached to an output shaft.

上記無段変速装置において、変速に必要な操作力を軽ろ
くできるように、しかも、駆動負荷の増大にかかわらず
ベルトスリップが生じないようにするのに、従来、第６
図に示すように、出力側ブー！Ｊ　ｉｔｏを構成する第
１及び第２回転体（ｌｌａ）、（ｌｌｂ）のうち、第１
回転体（ｌ１ｍ）を、出力軸＋１０１に摺動自在に取付
けると共に、スプリング０＠により第２回転体（１１ｂ
）側に摺動付勢し、又、第１回転体（ｌｌａ）の出力軸
Ｕに対する相対回転を可能にすると共に、その相対回転
が生じるに伴い第１回転体（１１＆）を第２回転体（ｌ
ｌｂ）側に摺動操作するカム機構のを、第１回転体（ｌ
ｌａ）と出力軸−の間に設けて、出力軸（１０１の駆動
負荷が増大するに伴い第１回転体（１１＆）がベルトα
２に自動的に押圧操作されるように、かつ負荷が増大す
るほど押圧力が増大するようにした自動加圧機構を構成
し、駆動負荷が設定値より小であると、ベルト０２）が
スプリング０５）の付勢力のみによって挟圧されるよう
に、かつ、駆動負荷が設定値以上になると、ベルトα２
がスズ９フフ０句の付勢力と、自動加圧機構により付与
される押圧力とによって挟圧されるように構成されてい
たために、駆動負荷に急激な低下変化が生じた際に、ベ
ルトスリップが生じ易くなっていた。　なぜならば、駆
動負荷が設定値以上である時には第１回転体（１１＆）
にそれを第２回転体（１ｌｂ）から離間させるべく作用
する犬なる加圧反力が作用するのであり、他方、前記加
圧機構にあっては、駆動負荷が設定値未満に低下するに
伴い加圧作用が急激に解除されるのであり、それ故に、
駆動負荷が急低下すると、第１回転体（１１＆）が前記
加圧反力のためにスプリング０５］全容易に変形させて
第２回転体（ｌｌｂ）から離間し、出カブ−Ｕ　ｔｉｌ
＋のベルト挟圧力が急激に低下するからである。In the above-mentioned continuously variable transmission, in order to reduce the operating force necessary for shifting and to prevent belt slip from occurring despite an increase in driving load, conventionally, a sixth method has been used.
As shown in the figure, the output side Boo! Of the first and second rotating bodies (lla) and (llb) constituting J ito, the first
The rotating body (l1m) is slidably attached to the output shaft +101, and the second rotating body (11b
) side, and also enables relative rotation of the first rotating body (lla) with respect to the output shaft U, and as the relative rotation occurs, the first rotating body (11&) is forced to slide toward the second rotating body (l
The cam mechanism that slides toward the first rotating body (lb) side is
1a) and the output shaft, and as the driving load of the output shaft (101 increases), the first rotating body (11 &)
An automatic pressing mechanism is configured so that the pressing force is increased as the load increases, and when the driving load is smaller than the set value, the belt 02) is automatically pressed. 05), and when the driving load exceeds the set value, the belt α2
Because the belt was configured to be compressed by a biasing force of 90% tin and a pressing force applied by an automatic pressurizing mechanism, belt slippage occurred when a sudden decrease in the drive load occurred. was becoming more likely to occur. This is because when the driving load is higher than the set value, the first rotating body (11&)
On the other hand, in the pressurizing mechanism, as the driving load decreases below the set value, The pressurizing effect is suddenly released, and therefore,
When the driving load suddenly decreases, the first rotary body (11 &) easily deforms the spring 05 due to the pressurizing reaction force and separates from the second rotary body (llb).
This is because the + belt clamping force decreases rapidly.

本発明の目的は、変速操作が軽ろくできると共に、駆動
負荷が増大してもベルトスリップが生じないようにし、
しかも、負荷の急低下に伴うベルトスリップをも防止で
きるようにすることにある。The purpose of the present invention is to enable easy gear shifting operations and to prevent belt slip from occurring even when driving load increases.
Furthermore, the purpose is to prevent belt slip caused by a sudden drop in load.

本発明の特徴構成は、旨記したベルト式無段変速装置に
おいて、前記スプリングの付勢力を前記第１回転体に伝
達するスリーブを、前記出力軸に一体回転及び摺切自在
に外底すると共に前記出力軸と第１回転体が相対回転す
るに伴いそれらの回転速度差が増大するほど摺動ス）ロ
ーフが大となる状態で前記スリーブをスプリング付勢力
増大側６Ｃ摺動操作するカム機構を、前記スリーブと第
１回転体の間に設けた事にある。The characteristic configuration of the present invention is that, in the belt-type continuously variable transmission described above, a sleeve for transmitting the biasing force of the spring to the first rotating body is provided with an outer bottom so as to be integrally rotatable and slidable on the output shaft. A cam mechanism that slides the sleeve on the spring urging force increasing side 6C in a state where the sliding loaf becomes larger as the rotational speed difference between the output shaft and the first rotating body increases as the output shaft and the first rotating body rotate relative to each other. , provided between the sleeve and the first rotating body.

つまり、前記スリーブ及びカム機構を設けることにより
、駆動負荷が増大するほど挟圧力が増大する状態に出力
プーリのベルト挟圧力が自動調節されるので、変速操作
が軽操作力でできるように、しかも、駆動負荷が増大し
てもベルトスリップが生じないようにでき、その上、ベ
ルト挟持圧を増大させるのにスプリングの付勢力を増大
させると、駆動負荷が急低下した際に第１回転体がベル
ト加圧反力によって第２回転体から急激に離間操作され
ることが付勢力の大となっているスプリングの大なる抵
抗力によって防止されるので、駆動負荷の急低下にかか
わらずベルトスリップが生じないようにでき、全体とし
て、変速操作が軽快にできるとか操作構成を軽小なもの
にできるものを、伝動が負荷変動にかかわらず回転数の
安定した状態で確実に行われると共に、ベルト摩損が効
果的に防止される状態に構成できた。In other words, by providing the sleeve and cam mechanism, the belt clamping force of the output pulley is automatically adjusted to a state where the clamping force increases as the drive load increases, making it possible to perform gear shifting operations with light operating force. , it is possible to prevent belt slip from occurring even when the driving load increases, and in addition, by increasing the biasing force of the spring to increase the belt clamping pressure, the first rotating body can be prevented from occurring when the driving load suddenly decreases. The large resistance force of the spring, which has a large urging force, prevents the belt from being moved away from the second rotary body suddenly due to the reaction force, so the belt slips even if the driving load suddenly decreases. It is possible to prevent this from occurring, and as a whole, the speed change operation can be made light and the operation configuration can be made light and compact, and the transmission is performed reliably at a stable rotational speed regardless of load fluctuations, and belt wear and tear can be prevented. We were able to configure the system so that it is effectively prevented.

以下ｔ１本本発明実施例を図面に基いて説明する。Embodiments of the present invention will be described below with reference to the drawings.

第１図に示すように、左右一対の操向操作自在な前車輪
ｍ　、　（１１、及び、左右一対の駆動後車輪＋２１　
、　＋２１を備えさせると共に、原動部１８＋及びその
後方に配置した運転部（４１夫々を備えさせた自走車体
に、芝刈装Ｎ１６１を前後輪間に位置させた状態でリン
ク機構にょシ昇降操作自在に連結すると共に、自走車か
ら芝刈装置＋５１に回動力を伝達するように構成して、
乗用型芝刈機を構成しである。As shown in FIG. 1, a pair of left and right steerable front wheels m,
, +21, and a self-propelled vehicle body equipped with a driving part 18+ and a driving part (41) placed behind it, with the lawn mower N161 positioned between the front and rear wheels, the link mechanism can be freely operated up and down. and is configured to transmit rotational force from the self-propelled vehicle to the lawn mower +51,
It consists of a riding lawn mower.

エンジン（６）と、後車輪＋２１を前進２段、後進１段
に変速するギアトランスミッションのケース（７１との
間において、第２図に示すように、エンジン＋６１に連
動させた入力軸（８）に入力割りプーリ＋９１を、前記
ミッションへの出力軸ａαに出力割プーリ１１１）を夫
々取付けると共に、両プーリ［９１、ｔｏ）にわたって
伝動ベルトαツを巻回し、そして、出力側プーリｆ口１
を構成させてる第１回転体（１１＆）及び、第２回転体
（１１１））のうちの第１回転体（１１＆）を、出力軸
＋１０＋に一体回転及び摺動自在にスプライン外嵌させ
たスリーブαｊと、第２回転体（ｌｌｂ）のボス部を介
して出力軸間に摺動自在に取付けると共に、前記スリー
ブ圃、及び、このスリーブαｊに一端側が係入するよう
に第１回転体（ｌｌａ）に取付けた一対のピン！１４１
　、０４を介して第１回転体（１１＆）を第２回転体（
ｌｌｂ）に接近摺動付勢するスプリング鋼を、スリーブ
ａ１の一端側と、出力軸間にネジ止めしであるバネ受け
０１３１との間に介在させて、伝動ペルトロのに張力を
付与するように構成し、もって、入力割りプーリ）９）
を構成させである摺動自在な回転体（９ａ）のボス部に
軸受Ｏη及び輪体α槌を介して係止させであるホークα
鶏を揺動操作し、前記回転体（９＆）を固定側回転体（
９１））Ｋ接近・離間させて車体を変速走行させるよう
に、かつ、伝動ベル）［＋２１を伝動切り状態にしてミ
ッションへの伝動停止を行うようにしたベルト式無段変
速装置を構成しである。As shown in Figure 2, between the engine (6) and the gear transmission case (71) that shifts the rear wheels +21 to two forward speeds and one reverse speed, there is an input shaft (8) linked to the engine +61. Attach the input split pulley +91 to the output shaft aα to the transmission, and the output split pulley 111) to the output shaft aα to the transmission, and wind the transmission belt α2 over both pulleys [91, to).
A sleeve in which the first rotating body (11&) of the first rotating body (11 &) and the second rotating body (111) constituting the output shaft +10+ is fitted onto the output shaft +10+ with a spline so that it can rotate integrally and freely slide. αj and the second rotary body (llb) are slidably attached to each other between the output shaft via the boss portion of the second rotary body (llb), and the first rotary body (lla ) a pair of pins attached to! 141
, 04 to connect the first rotating body (11 &) to the second rotating body (
A spring steel that biases sliding toward the 1lb) is interposed between one end of the sleeve a1 and a spring receiver 0131 that is screwed between the output shafts, so as to apply tension to the transmission Peltro. Configure and have an input split pulley)9)
A hawk α is secured to the boss portion of a freely slidable rotating body (9a) through a bearing Oη and a wheel α mallet.
Rock the chicken and move the rotating body (9&) to the stationary rotating body (
91)) A belt-type continuously variable transmission device is configured so that the vehicle body moves at variable speeds by approaching and separating K, and the transmission belt (+21) is set to the transmission disengaged state to stop transmission to the transmission. be.

前記スリーブ圃の前記ピンＩの夫々に対する挿入部を、
第３図及び第４図に示す如き切欠き（１３ａ）にして、
第１回転体（ｌｌａ）と出力軸間の相対回転、及び、ス
リーブαｊの第１回転体（ｌｌａ）に対する摺動が大々
可能となるように構成しである。　そして、前記切欠き
夫々の内壁面の一部を、第３図及び第４図に示す如く、
出力軸Ｕの長手方向において、その軸芯と傾斜するカム
面側に形成すると共に、このカム面（ホ）に対接するロ
ーラ（２１１をピン０４Ｊに付設して、スリーブｒ１３
１を出力軸（【α及び第１回転体（１１１Ｌ）に対して
摺動操作するカム機構（２２）を構成し、もって、駆動
負荷が増大すると出力割プーリｎｔ）によるベルト挟圧
力が自動的に増大調節されるように、出力軸Ｕαと第１
回転体（ｌｌａ）が相対回転するに伴い、スリーブ１１
１が第４図に示す状態から第５図に示す状態に、すなわ
ちスプリングα〜側に摺動操作され、スプリング州を圧
Ｍ変形させてその付勢力を増大させるように、かつ、出
力軸１１１１と第１回転体（ｌｌａ）の回転速度差が増
大するほど、スリーブａ３の摺動操作ストロークが増大
されてスプリング０５１の付勢力が増大されるように構
成しである。An insertion portion for each of the pins I in the sleeve field,
With a notch (13a) as shown in FIGS. 3 and 4,
The structure is such that relative rotation between the first rotating body (lla) and the output shaft and sliding movement of the sleeve αj with respect to the first rotating body (lla) are possible. Then, as shown in FIGS. 3 and 4, a part of the inner wall surface of each of the notches is
In the longitudinal direction of the output shaft U, a roller (211) is attached to the pin 04J and formed on the cam surface side that is inclined with the axis of the output shaft U, and is in contact with the cam surface (E).
1 constitutes a cam mechanism (22) that slides against the output shaft ([α and the first rotating body (111L)), so that when the drive load increases, the belt clamping force by the output split pulley nt is automatically increased. The output shaft Uα and the first
As the rotating body (lla) rotates relative to each other, the sleeve 11
1 is slid from the state shown in FIG. 4 to the state shown in FIG. The structure is such that as the difference in rotational speed between the first rotating body (lla) and the first rotating body (lla) increases, the sliding operation stroke of the sleeve a3 is increased and the biasing force of the spring 051 is increased.

尚、本発明構成を実施するに当り、スリーブａ謙トピン
Ｉの保合によってプーリから出力軸叫に駆動力が伝動さ
れるので、第２回転体（ｉｌｂ）の方にもそれを第１回
転体（ｌｌａ）に接近摺動付勢するスプリングを作用さ
せると共に、このスプリングの付勢力調節を行わせるだ
めのスリーブ及びカム機構を設けたり、第２回転体（１
１１））を出力軸（１０１に相対回転自在に取付けても
よい。In carrying out the configuration of the present invention, since the driving force is transmitted from the pulley to the output shaft by the engagement of the sleeve a and the lower pin I, the driving force is also transmitted to the second rotating body (ilb) during the first rotation. A spring that biases the body (lla) to approach the body (lla) is provided, and a sleeve and a cam mechanism are provided to adjust the biasing force of this spring.
11)) may be relatively rotatably attached to the output shaft (101).

本発明による変速装置は、ｔ＋−転機、コンバイン、田
植機等の各種作業車や走行用以外の伝動系にも適用でき
る。The transmission device according to the present invention can be applied to various work vehicles such as t+-turning machines, combines, rice transplanters, etc., and to transmission systems other than those for traveling.

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

図面は本発明に係るベルト式無段変速装置の実施乃１．
＆ｉ、様奪輯示し、第１図は芝刈り機の側面図、第２図
は変速装置の断面図、第３図はスリーブの斜視図、第４
図及び第５図はスリーブ配設部の断面図、第６図は従来
構造の断面図である。 ■・・・・・・出力軸、（１１）・・・・・・出力割プ
ーリ、（ｌｌａ）・・・・・・第１回転体、（ｌｌｂ）
・・・・・・第２回転体、　ｆｌＢ！・・・・・・スリ
ーブ、−・・・・・・スプリング、の・・・・・・カム
機構。 特開昭５９−１７０５５４（４） 第　２　図 ８９）恭琵Ｊル９The drawings show implementation No. 1 of the belt type continuously variable transmission according to the present invention.
&i, Figure 1 is a side view of the lawn mower, Figure 2 is a sectional view of the transmission, Figure 3 is a perspective view of the sleeve, and Figure 4 is a side view of the lawn mower.
5 and 5 are cross-sectional views of the sleeve installation portion, and FIG. 6 is a cross-sectional view of the conventional structure. ■... Output shaft, (11)... Output split pulley, (lla)... First rotating body, (llb)
...Second rotating body, flB! ...Sleeve, - ...Spring, ...Cam mechanism. JP-A-59-170554 (4) No. 2 Figure 89) Kyobi Jle 9

Claims (1)

【特許請求の範囲】[Claims] 出力側ブー！Ｊ　＋Ｉｌｌにおいて第１回転体（ｌｌａ
）を第２回転体（ｉｉｂ）に接近するようにスプリング
Ｑｌにより摺動付勢すると共に、前記第１回転体（ｌｌ
ａ）を出力軸−に相対回転自在に取付けたベルト式無段
変速装置であって、前記スプリングα均の付勢力を前記
第１回転体（１１＆）に伝達するスリーブα３を、前記
出力軸Ｕに一体回転及び摺動自在に外嵌すると共に、前
記出力軸−と第１回転体（ｌｌａ）が相対回転するに伴
い、それらの回転速度差が増大するほど摺動ストローク
が大となる状態で前記スリーブ（Ｉ：４をスプリング付
勢力増大側に摺動操作するカム機構のを、前記スリーブ
＋１３１と第１回転体（１１＆）の間に設けであるベル
ト式無段変速装置。Output side boo! The first rotating body (lla
) to approach the second rotating body (iib) by a spring Ql, and the first rotating body (ll
a) is a belt-type continuously variable transmission device which is relatively rotatably attached to the output shaft U, and a sleeve α3 for transmitting the biasing force of the spring α to the first rotating body (11&) is connected to the output shaft U. The output shaft and the first rotating body (lla) are fitted externally so that they can rotate and slide freely, and as the output shaft and the first rotating body (lla) rotate relative to each other, the sliding stroke becomes larger as the rotational speed difference between them increases. A belt-type continuously variable transmission device in which a cam mechanism for sliding the sleeve (I:4) to increase the spring biasing force is provided between the sleeve +131 and the first rotating body (11&).
JP4643283A 1983-03-18 1983-03-18 Belt type stepless transmission device Pending JPS59170554A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4643283A JPS59170554A (en) 1983-03-18 1983-03-18 Belt type stepless transmission device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4643283A JPS59170554A (en) 1983-03-18 1983-03-18 Belt type stepless transmission device

Publications (1)

Publication Number Publication Date
JPS59170554A true JPS59170554A (en) 1984-09-26

Family

ID=12746986

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4643283A Pending JPS59170554A (en) 1983-03-18 1983-03-18 Belt type stepless transmission device

Country Status (1)

Country Link
JP (1) JPS59170554A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100342062B1 (en) * 1999-07-02 2002-06-27 이계안 Pully for CVT
US6733406B2 (en) * 2001-02-23 2004-05-11 Kawasaki Jukogyo Kabushiki Kaisha Variable-speed V-belt drive for vehicle

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100342062B1 (en) * 1999-07-02 2002-06-27 이계안 Pully for CVT
US6733406B2 (en) * 2001-02-23 2004-05-11 Kawasaki Jukogyo Kabushiki Kaisha Variable-speed V-belt drive for vehicle

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