以下，一面參照圖式一面對本發明中提出之踏力輔助系統之一實施形態進行說明。圖1係作為實施形態之一例之電動輔助自行車1A之側視圖。圖2A係表示第1實施形態之電動輔助自行車1A之構成之方塊圖。於圖2A中粗實線表示動力之傳遞，細實線表示信號或電流。電動輔助自行車1A具有用以輔助騎乘者之踏力之踏力輔助系統。踏力輔助系統由下述電動馬達21、控制裝置30A、馬達驅動裝置39、及感測器等電力組件構成。 [第1實施形態] 如圖1所示，電動輔助自行車1A具有曲柄軸2。於曲柄軸2之兩端安裝有踏板2a。曲柄軸2係由座部管11之下端支持。於座部管11之上端固定有座部18。於電動輔助自行車1A之前部，設置有：把手柱8；把手7，其固定於把手柱8之上部；前叉19，其固定於把手柱8之下部；及前輪9，其由前叉19之下端支持。把手柱8由設置於車架17之前端之頭管17a支持。 電動輔助自行車1A具有由用以輔助騎乘者施加至踏板2a之力(踏力)之電動馬達21(參照圖2A)或減速機25等構成之驅動單元10。電動馬達21係藉由自電池22(參照圖1)供給之電力而驅動。於電動輔助自行車1A之例中，電池22安裝於座部管11之後側，驅動單元10配置於曲柄軸2之後側。電池22與驅動單元10之佈局並不限定於電動輔助自行車1A之例，可適當變更。 如圖2A所示，經由踏板2a施加至曲柄軸2之動力(轉矩)經由單向離合器23而傳遞至合力傳遞機構24。又，於電動輔助自行車1A之例中，自電動馬達21輸出之動力(輔助力)經由減速機25與單向離合器26而傳遞至合力傳遞機構24。合力傳遞機構24將施加至曲柄軸2之動力與自電動馬達21輸出之動力合成。合力傳遞機構24例如由軸、設置於軸上之旋轉構件、鏈條5(圖1)等構成。於合力傳遞機構24之一例中，2個動力係藉由輸入至共用之軸或共用之旋轉構件而合成。作為其他例，將2個動力之兩者輸入至鏈條5，並加以合成。由合力傳遞機構24合成之動力如圖2A所示，例如經由變速機構27與單向離合器28而傳遞至後輪6。電動輔助自行車1A亦可不具有變速機構27。 電動輔助自行車1A具有用以檢測騎乘者施加至踏板2a之踏力之感測器。該感測器如圖2A所示，例如為輸出與曲柄軸2之轉矩相應之信號之轉矩感測器41。轉矩感測器41例如為設置於曲柄軸2之磁應變式之感測器，但其種類並不特別限定。又，電動輔助自行車1A具有：馬達旋轉感測器(編碼器)42，其輸出與電動馬達21之旋轉速度相應之信號；前輪旋轉感測器43，其輸出與前輪9之旋轉速度相應之信號；及曲柄旋轉感測器45，其輸出與曲柄軸2之旋轉位置相應之信號。該等感測器41、42、43、45之輸出信號輸入至控制電動馬達21之控制裝置30A。 又，電動輔助自行車1A具有使用者可操作之操作部46。操作部46將與使用者之操作相應之信號輸出至控制裝置30A。如下所述，控制裝置30A亦可具有2種控制模式。第1控制模式為於車輛之加速度高於閾值之加速狀態下使自電動馬達21輸出之動力(輔助力)下降之模式。第2控制模式為不進行依據加速度與閾值之比較結果之輔助力之降低(於第1控制模式中執行之處理)之模式。控制裝置30A根據自操作部46輸入之信號，選擇性地執行第1控制模式與第2控制模式。藉此，使用者可選擇2種控制模式。操作部46之一例為顯示對使用者提供之選項(第1控制模式/第2控制模式)之顯示器與受理使用者之選擇之按鈕。作為其他例，操作部46亦可為能夠實現打開操作/關閉操作之按鈕。例如，亦可於打開狀態下選擇第1控制模式，於關閉狀態下執行第2控制模式。 進而，電動輔助自行車1A具有用以檢測車輛之加速度之加速度感測器51。加速度感測器51以輸出與車體之前後方向之加速度相應之信號之方式設置。 控制裝置30A具有：記憶體，其保持電動馬達21之控制之程式或映射表；及微處理器，其執行上述程式。控制裝置30A基於轉矩感測器41之輸出而檢測騎乘者之踏力，控制電動馬達21以使電動馬達21輸出與踏力相應之動力(輔助力)。控制裝置30A將與騎乘者之踏力相應之指令值輸出至馬達驅動裝置39。馬達驅動裝置39接收電池22之電力並將與指令值相應之電力供給至電動馬達21。馬達驅動裝置39例如由轉換器或反相器等構成。控制裝置30A亦可於電動馬達21之控制中，利用基於前輪旋轉感測器43之輸出信號而檢測之車速、或基於曲柄旋轉感測器45之輸出信號而檢測之曲柄軸2之旋轉位置或旋轉速度。 第1實施形態之控制裝置30A於車輛之加速度高於閾值之加速狀態下，相較車輛之加速度小於閾值之通常狀態而降低自電動馬達21輸出之動力(輔助力)。藉由此，可抑制騎乘者未意圖之加速，可提高行駛時之舒適性。控制裝置30A亦可僅於經由操作部46選擇第1控制模式時，執行此種控制。 圖2B係表示控制裝置30A之處理之方塊圖。如該圖所示，控制裝置30A具有輔助力算出部31A、馬達控制部32、及加速判定部33，作為其功能。該等功能係藉由微處理器執行儲存於控制裝置30A所具有之記憶體之程式而實現。 加速判定部33判斷車輛是否急加速。具體而言，加速判定部33判斷車輛之加速度是否高於閾值，於車輛之加速度高於閾值之情形時判斷為車輛處於加速狀態(將該閾值稱為「加速判定閾值」)。又，加速判定部33於車輛之加速度低於加速判定閾值之情形時判斷為車輛處於通常狀態。加速判定部33例如基於加速度感測器51之輸出信號而檢測車輛之加速度。加速判定部33亦可代替加速度感測器51之輸出信號，基於前輪旋轉感測器43之輸出信號而算出車輛之加速度。 加速判定部33如圖2B所示，亦可具有根據車輛之運轉狀態而變更加速判定閾值之閾值設定部33a。而且，加速判定部33亦可判斷車輛之加速度是否高於由閾值設定部33a設定之加速判定閾值。閾值設定部33a為了設定閾值而利用之運轉狀態包含車速、或施加至踏板2a之踏力等。例如，若車速變高，則閾值設定部33a使閾值下降。控制裝置30A亦可檢測電池22之輸出電壓。於該情形時，閾值設定部33a亦可基於電池22之輸出電壓而設定閾值。例如，閾值設定部33a亦可於電池22之輸出電壓下降之情形時，使閾值下降。藉由此，可有效地抑制於電池22之輸出電壓下降之狀態下之急加速時電動馬達21驅動。再者，作為其他例，閾值例如亦可為預先設定之固定值。 輔助力算出部31A算出電動馬達21應輸出之動力(輔助力)，即目標輔助力。輔助力算出部31A算出與施加至踏板2a之踏力及車速相應之目標輔助力。例如，輔助力算出部31A參照表示輔助力、踏力及車速之關係之映射表或關係式，算出與經由感測器檢測到之踏力及車速相應之輔助力(以下，將該輔助力稱為通常輔助力)。於電動輔助自行車之一例中，使輔助率(輔助率＝輔助力/踏力)與車速對應而預先儲存於記憶體。輔助力算出部31A將與由感測器檢測到之車速對應之輔助率乘以踏力，並將該相乘之結果設為通常輔助力。於第1實施形態中，於加速判定部33之處理之結果判斷為車輛不處於加速狀態時，即車輛處於通常狀態時，控制裝置30A將通常輔助力設為目標輔助力。 輔助力算出部31A如圖2B所示，包含輔助力降低部31a。輔助力降低部31a於車輛處於加速狀態時，將低於通常輔助力之輔助力設定為目標輔助力。例如，輔助力降低部31a將通常輔助力乘以係數(例如，係數＜1)，並將該相乘之結果設為目標輔助力。作為其他例，亦可將根據車速而設定之輔助率與用以使輔助力降低之係數(例如，係數＜1)乘以踏力，並將該相乘之結果設為目標輔助力。 於進而其他例中，輔助力降低部31a亦可自通常輔助力減去固定值，並將該減算之結果設為目標輔助力。 作為進而其他例，輔助力降低部31a亦可於車輛處於加速狀態時，參照表示低於通常輔助力之輔助力、踏力、及車速之關係之映射表或關係式，將自該等之映射表或關係式所獲得之輔助力設定為目標輔助力。該映射表或關係式亦例如預先儲存於控制裝置30A之記憶體。 作為進而其他例，輔助力降低部31a亦可將低於可於通常狀態設定之目標輔助力之最小值之輔助力設定為目標輔助力。例如，輔助力降低部31a亦可將0設定為目標輔助力。 馬達控制部32將與由輔助力算出部31A之處理算出之目標輔助力相應之指令值輸出至馬達驅動裝置39。又，馬達控制部32基於馬達旋轉感測器42之輸出信號而算出電動馬達21之旋轉速度，並監視電動馬達21是否進行與指令值相應之適當之驅動。 再者，於控制裝置30A具有2種控制模式之形態中，加速判定部33與輔助力降低部31a僅於經由操作部46選擇第1控制模式時執行。於選擇第2控制模式時，加速判定部33與輔助力降低部31a不執行，而是將藉由輔助力算出部31A算出之通常輔助力設定為目標輔助力。即，控制裝置30A於第2控制模式中，不將加速度感測器51之輸出利用於目標輔助力之算出。藉由使用者進行之控制模式之選擇亦可未必成為可能。即，控制裝置30A亦可恆常性地執行第1控制模式中之控制。 圖2C係表示控制裝置30A執行之處理之一例之流程圖。控制裝置30A以特定之週期(例如，數十msec)重複執行該圖所示之處理。於控制裝置30A具有2種控制模式之形態中，該流程圖之處理係於選擇第1控制模式之情形時執行。 控制裝置30A基於轉矩感測器41之輸出信號而檢測施加至踏板2a之踏力，並基於前輪旋轉感測器43之輸出信號而檢測車速(S101)。其次，輔助力算出部31A算出與經檢測之踏力及車速相應之通常輔助力(S102)。 又，加速判定部33基於加速度感測器51(或前輪旋轉感測器43)之輸出信號而檢測車輛之加速度(S103)，並判定經檢測之加速度是否大於加速判定閾值(S104)。S104之處理中所使用之加速判定閾值例如係藉由上述閾值設定部33a，根據車輛之運轉狀態而設定之閾值。於加速度高於加速判定閾值之情形時，即車輛處於加速狀態時，藉由輔助力降低部31a之處理，而將低於S102中算出之通常輔助力之輔助力設定為目標輔助力(S105)。 另一方面，於加速度不高於加速判定閾值之情形時，即車輛處於通常狀態時，將輔助力算出部31A於S102中算出之通常輔助力設為目標輔助力(S106)。然後，馬達控制部32將與S105或S106中算出之目標輔助力相應之指令值輸出至馬達驅動裝置39(S107)。以上為控制裝置30A執行之處理之例。 再者，閾值設定部33a亦可使加速狀態下利用之加速判定閾值與通常狀態下利用之加速判定閾值不同。例如，加速狀態下利用之閾值亦可低於通常狀態下之利用之加速判定閾值。藉由此，可抑制於車輛之加速度為接近閾值之值之情形時S104之判定結果頻繁地切換。例如，亦可於1個循環前之處理中判斷為車輛處於通常狀態之情形時利用第1值作為加速判定閾值，於1個循環前之處理中判斷為車輛處於加速狀態之情形時，利用低於第1值之第2閾值作為加速判定閾值。 亦可代替圖2C所示之例，輔助力算出部31A於車輛自加速狀態返回至通常狀態時，使目標輔助力逐漸接近通常輔助力。例如，輔助力算出部31A於車輛自加速狀態返回至通常狀態時，亦將通常輔助力或輔助率乘以係數，並將該相乘之結果設為目標輔助力。此時，亦可使係數自小於1之值逐漸接近1。藉由此，可抑制於車輛自加速狀態返回至通常狀態時，輔助力驟然上升。車輛自加速狀態返回至通常狀態時之處理並不限定於此。例如，輔助力算出部31A亦可於車輛自加速狀態返回至通常狀態時，直接再次開始設定通常輔助力作為目標輔助力之處理。 控制裝置30A亦可不具有加速判定部33。即，輔助力算出部31A亦可代替圖2C所示之S104、S105、S106之處理，將根據車輛之加速度而設定之係數乘以通常輔助力或輔助率。該係數係與車輛之加速度對應而預先儲存於記憶體，例如與車輛之加速度對應而連續性地規定。又，該係數係以關於相對較高之加速度之輔助力小於關於相對較低之加速度之輔助力之方式規定。即，該係數係以關於相對較高之加速度之係數(加速狀態下之係數)小於關於相對較低之加速度之係數(通常狀態下之係數)之方式規定。若利用此種係數，則可不進行S104之判定，於加速狀態下相較通常狀態而降低輔助力。又，可根據加速度之變化而使輔助力連續性地變化。藉此，可提高車輛之乘坐感覺。 [第2實施形態] 第2實施形態之控制裝置利用車輛之加速度來判斷後輪6是否打滑。而且，控制裝置於後輪6打滑之狀態下，與未產生打滑之通常狀態相比降低自電動馬達21輸出之輔助力。藉由此，可提高砂石路或泥路等摩擦係數較低之路面上之加速性或舒適性。 圖3A係表示第2實施形態之電動輔助自行車1B、及電動輔助自行車1B所具備之踏力輔助系統之構成之方塊圖。圖3B係表示電動輔助自行車1B所具備之控制裝置30B之處理之方塊圖。於該等圖中，對與第1實施形態相同之裝置及功能標註相同符號。以下，關於與第1實施形態相同之事項，省略其說明。 如圖3A所示，電動輔助自行車1B具有輸出與後輪6之旋轉速度相應之信號之後輪旋轉感測器44。又，電動輔助自行車1B具有上述加速度感測器51。加速度感測器51係與第1實施形態中所說明者相同，輸出與車體之前後方向之加速度相應之信號。 如圖3B所示，控制裝置30B具有輔助力算出部31B、上述馬達控制部32、及打滑判定部34，作為其功能。該等功能係藉由微處理器執行儲存於控制裝置30B所具有之記憶體之程式而實現。 於後輪6打滑時，後輪6之旋轉加速度與車輛之加速度相比較大。因此，打滑判定部34利用基於後輪旋轉感測器44之輸出信號而算出之後輪6之旋轉加速度與車輛之實際之加速度，判斷後輪6是否打滑。例如，打滑判定部34於車輛之加速度小於第1閾值，另一方面後輪6之旋轉加速度大於第2閾值之情形時，判斷為後輪6打滑。打滑判定部34例如基於加速度感測器51之輸出信號而檢測車輛之實際之加速度。亦可代替其，打滑判定部34基於前輪旋轉感測器43之輸出信號，而檢測車輛之實際之加速度。 作為其他例，打滑判定部34亦可將基於感測器51、43之輸出而檢測到之車輛之加速度之維度與基於後輪旋轉感測器44之輸出而檢測到之後輪6之旋轉加速度之維度利用後輪6之直徑統一，將維度經統一之2個加速度進行比較。即，打滑判定部34利用後輪6之直徑(r)算出與自感測器51、43之輸出信號所獲得之車輛之實際之加速度(dv/dt)對應之後輪6之旋轉加速度(dω/dt)(dω/dt＝(dv/dt)/r)。而且，亦可將與車輛之實際之加速度對應之後輪6之旋轉加速度與自後輪旋轉感測器44之力所獲得之後輪6之旋轉加速度進行比較。然後，於2個旋轉加速度之差大於閾值之情形時，打滑判定部34亦可判斷為後輪6打滑。作為進而其他例，打滑判定部34亦可基於後輪旋轉感測器44之輸出與後輪6之直徑而算出車輛之加速度，並將自後輪旋轉感測器44之輸出所獲得之車輛之加速度與自感測器51、43之輸出信號所獲得之加速度進行比較。而且，於其差大於閾值之情形時，打滑判定部34亦可判斷為後輪6打滑。 與第1實施形態相同，打滑判定部34利用之閾值亦可根據車輛之運轉狀態而變更。此處，運轉狀態例如包含車速。例如，若車速變高，則打滑判定部34使閾值下降。 輔助力算出部31B與第1實施形態相同，算出與施加至踏板2a之踏力及車速相應之輔助力。例如，輔助力算出部31B參照表示輔助力、踏力及車速之關係之映射表或關係式，算出與經檢測之踏力及車速相應之通常輔助力。於一例中，輔助力算出部31B將根據車速而設定之係數乘以踏力，並將該相乘之結果設為通常輔助力。輔助力算出部31B於車輛處於通常狀態(即不產生後輪6之打滑之狀態)時，將通常輔助力設為目標輔助力。 輔助力算出部31B包含輔助力降低部31b。輔助力降低部31b於後輪6打滑時，將低於通常輔助力之輔助力設定為目標輔助力。例如，輔助力降低部31b將通常輔助力乘以係數(例如，係數＜1)，並將該相乘之結果設為目標輔助力。作為其他例，輔助力降低部31b亦可將根據車速而設定之上述輔助率與輔助力降低用之係數(例如，係數＜1)乘以踏力，並將該相乘之結果設為目標輔助力。 作為進而其他例，輔助力降低部31b亦可自通常輔助力減去固定值，並將該減算之結果設為目標輔助力。 作為進而其他例，輔助力降低部31b亦可參照表示低於通常輔助力之輔助力、施加至踏板2a之踏力、及車速之關係之映射表或關係式，將自映射表或關係式所獲得之輔助力設定為目標輔助力。 輔助力降低部31b亦可設定0作為目標輔助力。換言之，輔助力降低部31b於產生後輪6之打滑之情形時，亦可使電動馬達21之驅動停止。 控制裝置30B亦與控制裝置30A相同，具有2種控制模式。於第1控制模式中，控制裝置30B判斷後輪6是否打滑，於後輪6打滑之狀態下降低自電動馬達21輸出之輔助力。於第2控制模式中，控制裝置30B不進行依據後輪6之打滑判定之輔助力之降低(於第1控制模式中執行之處理)。即，控制裝置30B於第2控制模式中，不將加速度感測器51之輸出利用於目標輔助力之算出。如圖3A所示，控制裝置30B亦與控制裝置30A相同，具有操作部46。控制裝置30B亦可根據自操作部46輸入之信號選擇性地執行第1控制模式與第2控制模式。藉由使用者進行之控制模式之選擇亦可未必成為可能。即，控制裝置30B亦可恆常性地執行第1控制模式中之控制。 於控制裝置30B具有2種控制模式之形態中，打滑判定部34與輔助力降低部31b僅於經由操作部46選擇第1控制模式時執行。於選擇第2控制模式時，打滑判定部34與輔助力降低部31b不執行，而是將藉由輔助力算出部31B算出之通常輔助力設定為目標輔助力。 圖3C係表示控制裝置30B執行之處理之一例之流程圖。控制裝置30B以特定之週期(例如，數十msec)重複執行該圖所示之一系列之處理。於控制裝置30B具有2種控制模式之形態中，該流程圖之處理係於選擇第1控制模式之情形時執行。 控制裝置30B基於轉矩感測器41之輸出信號而檢測施加至踏板2a之踏力，基於前輪旋轉感測器43之輸出信號而檢測車速(S201)。其次，輔助力算出部31B算出與踏力及車速相應之通常輔助力(S202)。 又，打滑判定部34基於加速度感測器51(或前輪旋轉感測器43)之輸出信號而檢測車輛之加速度(S203)。又，打滑判定部34基於後輪旋轉感測器44之輸出信號而算出後輪6之旋轉加速度(S204)。而且，打滑判定部34利用基於後輪旋轉感測器44之輸出信號算出之後輪6之旋轉加速度與基於加速度感測器51(或前輪旋轉感測器43)之輸出信號算出之加速度，判斷後輪6是否打滑(S205)。於後輪6打滑之情形時，輔助力降低部31b將低於通常輔助力之輔助力設定為目標輔助力(S206)。 另一方面，於不產生後輪6之打滑之情形時，輔助力算出部31B將S202中算出之通常輔助力設為目標輔助力(S208)。然後，馬達控制部32將與目標輔助力相應之指令值輸出至馬達驅動裝置39(S207)。 於控制裝置30B之處理之一例中，輔助力算出部31B與輔助力算出部31A相同，於自後輪6打滑之狀態返回至通常狀態時，亦可使目標輔助力逐漸接近通常輔助力。例如，輔助力算出部31B將通常輔助力乘以係數，並將該相乘之結果設為目標輔助力。此時，輔助力算出部31B亦可使係數自低於1之值逐漸接近1。自後輪6打滑之狀態返回至通常狀態時之處理並不限定於此。例如，輔助力算出部31B亦可於返回至通常狀態時，直接再次開始將通常輔助力設定為目標輔助力之處理。 [第3實施形態] 於第3實施形態中，踏力輔助系統具有用以檢測車輛於坡道行駛之傾斜感測器，作為加速度感測器。傾斜感測器具體而言為檢測車體之螺距角(以沿著車體之左右方向之軸為中心之車體之傾斜角)之感測器。控制裝置於車輛於坡道行駛之情形時，與車輛於平坦路行駛之情形時相比，將自電動馬達21輸出之輔助力增加，或降低。藉由此，於車輛於例如上坡行駛之情形時，可自動地獲得較大之輔助力，可實現舒適之行駛，又，可抑制於車輛於下坡行駛之情形時，不必要之電力消耗。 圖4A係表示第3實施形態之電動輔助自行車1C、及電動輔助自行車1C所具備之踏力輔助系統之構成之方塊圖。圖4B係表示電動輔助自行車1C所具有之控制裝置30C之處理之方塊圖。於該等圖中，對與第1實施形態相同之裝置及功能，標註相同符號。以下，關於與第1實施形態相同之事項，省略其說明。 如圖4A所示，電動輔助自行車1C具有傾斜感測器52。作為傾斜感測器52，可利用1軸、2軸、或3軸之加速度感測器。傾斜感測器52之加速度之檢測方向係以傾斜感測器52之輸出信號根據車體之螺距角而變化之方式設定。例如，傾斜感測器52之加速度之檢測方向為車體之前後方向。於將檢測方向設定為該方向之情形時，例如於車輛處於上坡時，由傾斜感測器52檢測之車體之向後方之加速度(重力)增大。傾斜感測器52之加速度之檢測方向亦可為車體之前後方向與車體之左右方向。進而，傾斜感測器52之加速度之檢測方向亦可為車體之左右方向與上下方向。 如圖4B所示，控制裝置30C具有輔助力算出部31C、上述馬達控制部32、及坡道判定部35，作為其功能。該等功能係藉由微處理器執行儲存於控制裝置30C之記憶體之程式而實現。 坡道判定部35基於傾斜感測器52之輸出信號而算出車體之螺距角。即，坡道判定部35基於由傾斜感測器52檢測之車體之加速度(重力)而算出車體之螺距角。而且，坡道判定部35基於經算出之螺距角而判斷車輛是否於坡道行駛。更具體而言，坡道判定部35基於螺距角而判斷車輛是否於上坡行駛。例如，於將以車體之前部變高之方式車體傾斜之情形時之螺距角之符號設為正之情形時，坡道判定部35於螺距角大於閾值(閾值＞0)之情形時，判斷為車輛於坡道行駛(以下將該閾值稱為上坡判定閾值)。又，坡道判定部35亦可基於螺距角而判斷車輛是否於下坡行駛。例如，於將以車體之後部變高之方式車體傾斜之情形時之螺距角之符號設為負之情形時，坡道判定部35於經算出之螺距角小於閾值(閾值＜0)之情形時，亦可判斷為車輛於下坡行駛(以下將該閾值稱為下坡判定閾值)。 輔助力算出部31C與第1實施形態之輔助力算出部31A相同，算出與施加至踏板2a之踏力及車速相應之輔助力。例如，輔助力算出部31C參照表示輔助力、踏力及車速之關係之映射表或關係式，算出與經檢測之踏力及車速相應之通常輔助力。於一例中，輔助力算出部31C將根據車速而設定之輔助率乘以踏力，並將該相乘之結果設為通常輔助力。輔助力算出部31C於車輛不於上坡或下坡行駛時，換言之於車輛於平坦路行駛時，將通常輔助力設為目標輔助力。 輔助力算出部31C包含於車輛於上坡行駛之情形時增加輔助力之輔助力增大部31c。輔助力增大部31c於車輛於上坡行駛之情形時，控制電動馬達21以使電動馬達21輸出大於通常輔助力之輔助力。例如，輔助力增大部31c將通常輔助力乘以係數(例如，係數＞1)，並將該相乘之結果設為目標輔助力。作為其他例，輔助力算出部31C亦可將根據車速而設定之輔助率與係數(例如，係數＞1)乘以踏力，並將該相乘之結果設為目標輔助力。 作為進而其他例，輔助力增大部31c亦可將通常輔助力加上固定值，並將該加法之結果設為目標輔助力。 作為進而其他例，亦可將上坡用之映射表或關係式預先儲存於記憶體。於該映射表或關係式中，表示有高於通常輔助力之輔助力、踏力、及車速之關係，輔助力增大部31c亦可參照該等映射表或關係式算出目標輔助力。 輔助力增大部31c算出之目標輔助力亦可根據上坡之傾斜，即根據車體之螺距角而變大。例如，輔助力增大部31c利用之上述係數根據車體之螺距角而變大。藉由此，即便於陡峭之上坡行駛之情形時，亦可順利地行駛，可提高行駛時之舒適性。係數並不限定於此，亦可為固定值。 輔助力算出部31C包含於車輛於下坡行駛之情形時降低輔助力之輔助力降低部31d。輔助力降低部31d於車輛於下坡行駛之情形時，控制電動馬達21以使電動馬達21所輸出之輔助力小於通常輔助力。於一例中，輔助力降低部31d亦可使電動馬達21之驅動停止。例如，輔助力降低部31d亦可使自馬達驅動裝置39向電動馬達21之電力供給停止。 輔助力降低部31d亦可將低於通常輔助力之輔助力設定為目標輔助力。例如，輔助力降低部31d亦可將通常輔助力乘以係數(例如，係數＜1)，並將該相乘之結果設定為目標輔助力。作為其他例，輔助力降低部31d亦可將根據車速而設定之輔助率與係數(例如，係數＜1)乘以踏力，並將該相乘之結果設為目標輔助力。 作為進而其他例，輔助力降低部31d亦可自通常輔助力減去固定值，並將該減算之結果設為目標輔助力。 作為進而其他例，亦可將下坡用之映射表或關係式預先儲存於記憶體。於該映射表或關係式中，表示有低於通常輔助力之輔助力、踏力、及車速之關係，輔助力降低部31d亦可參照該等映射表或關係式算出目標輔助力。輔助力降低部31d亦可設定0作為目標輔助力。 輔助力降低部31d算出之目標輔助力亦可根據下坡之傾斜，即根據車體之螺距角而變小。例如，輔助力降低部31d利用之係數根據螺距角而變小(即，係數接近0)。係數並不限定於此，亦可為固定值。 控制裝置30C亦與控制裝置30A相同，具有2種控制模式。於第1控制模式中，控制裝置30C判斷車輛是否於坡道行駛，於車輛於坡道行駛之情形時，將自電動馬達21輸出之輔助力增加、或降低。於第2控制模式中，控制裝置30C不進行依據道路之傾斜之輔助力之增減(於第1控制模式中執行之處理)。即，控制裝置30C於第2控制模式中，不將傾斜感測器52之輸出利用於目標輔助力之算出。控制裝置30C亦如圖4A所示，具有操作部46。控制裝置30C亦可根據自操作部46輸入之信號選擇性地執行第1控制模式與第2控制模式。藉由使用者進行之控制模式之選擇亦可未必成為可能。即，控制裝置30C亦可恆常性地執行第1控制模式中之控制。 於控制裝置30C具有2種控制模式之形態中，坡道判定部35、輔助力增大部31c及輔助力降低部31d僅於經由操作部46選擇第1控制模式時執行。於選擇第2控制模式時，坡道判定部35之處理與輔助力增大部31c與輔助力降低部31d不執行，而是將藉由輔助力算出部31C算出之通常輔助力設定為目標輔助力。 圖4C係表示控制裝置30C執行之處理之一例之流程圖。控制裝置30C以特定之週期(例如，數十msec)重複執行該圖所示之一系列之處理。於控制裝置30C具有2種控制模式之形態中，該流程圖之處理係於選擇第1控制模式之情形時執行。 控制裝置30C基於轉矩感測器41之輸出信號而檢測施加至踏板2a之踏力，基於前輪旋轉感測器43之輸出信號而檢測車速(S301)。其次，輔助力算出部31C算出與踏力及車速相應之通常輔助力(S302)。 又，坡道判定部35基於傾斜感測器52之輸出信號而檢測螺距角(S303)。而且，坡道判定部35判定螺距角是否大於上坡判定閾值(S304)。此處，於螺距角大於上坡判定閾值之情形時，即於車輛於上坡行駛之情形時，輔助力增大部31c增加輔助力。具體而言，輔助力增大部31c將高於通常輔助力之輔助力設定為目標輔助力(S305)。例如，將根據車速而設定之輔助率與係數(例如，係數＞1)乘以踏力，並將該相乘之結果設為目標輔助力。 於螺距角不大於上坡判定閾值之情形時，坡道判定部35判定螺距角是否小於下坡判定閾值(S307)。於螺距角小於下坡判定閾值之情形時，即於車輛於下坡行駛之情形時，輔助力降低部31d使電動馬達21之驅動停止(S308)。於螺距角不小於下坡判定閾值之情形時，輔助力算出部31C將通常輔助力設定為目標輔助力(S309)。馬達控制部32將與經設定之目標輔助力相應之指令值輸出至馬達驅動裝置39(S306)。 再者，控制裝置30C亦可未必具有坡道判定部35。於該情形時，亦可將表示螺距角與係數之關係之關係式或映射表預先儲存於記憶體，輔助力算出部31C利用與經檢測之螺距角對應之係數，增加通常輔助力，或降低通常輔助力。 [第4實施形態] 於第4實施形態中，踏力輔助系統具備用以檢測向左右方向之車體之傾斜之感測器。而且，控制裝置基於車體之傾斜而檢測車體之傾倒，於檢測到車體之傾倒時限制電動馬達21之驅動。藉由此，可抑制於車輛傾倒之狀態下，不必要地消耗電力。 圖5A係表示第4實施形態之電動輔助自行車1D、及電動輔助自行車1D所具備之踏力輔助系統之構成之方塊圖。圖5B係表示電動輔助自行車1D所具有之控制裝置30D之處理之方塊圖。於該等圖中，對與第1實施形態相同之裝置及功能，標註相同符號。以下，關於與第1實施形態相同之事項，省略其說明。 如圖5A所示，電動輔助自行車1D具有傾斜感測器53。作為傾斜感測器53，可利用1軸、2軸、或3軸之加速度感測器。傾斜感測器53之加速度之檢測方向係以傾斜感測器53之輸出信號根據車體之向左右方向之傾斜(即側傾角(roll angle))而變化之方式設定。例如，傾斜感測器52之加速度之檢測方向為車體之左右方向。傾斜感測器52之加速度之檢測方向除了車體之左右方向以外，亦可包含前後方向或上下方向。 如圖5B所示，控制裝置30D具有輔助力算出部31D、上述馬達控制部32、及傾倒判定部36，作為其功能。該等功能亦藉由微處理器執行儲存於控制裝置30D之記憶體之程式而實現。 傾倒判定部36基於傾斜感測器53之輸出信號而檢測車體之向左右方向之傾斜角(側傾角度)。傾倒判定部36基於傾斜角而判斷車輛是否傾倒。例如，傾倒判定部36於傾斜角大於閾值之情形時，判斷為車輛傾倒(以下將該閾值稱為傾倒判定閾值)。傾倒判定部36亦可基於車體之傾斜角與車速而判斷車輛是否傾倒。例如，傾倒判定部36亦可於車速低於閾值且傾斜角大於傾倒判定閾值之情形時，判斷為車輛傾倒。 控制裝置30D於檢測到車體傾倒時限制電動馬達21之驅動。具體而言，控制裝置30D於檢測到車體傾倒時使電動馬達21之驅動停止。具體而言，馬達控制部32使向馬達驅動裝置39之指令值之輸出停止，或使自馬達驅動裝置39向電動馬達21之電力供給停止。 輔助力算出部31D與第1實施形態之輔助力算出部31A相同，算出與施加至踏板2a之踏力及車速相應之輔助力。例如，輔助力算出部31D參照表示輔助力、踏力及車速之關係之映射表或關係式，算出與經檢測之踏力及車速相應之目標輔助力。於一例中，輔助力算出部31D將根據車速而設定之輔助率乘以踏力，並將該相乘之結果設為目標輔助力。傾倒判定部36之處理之結果，於檢測到車體之傾倒時，輔助力算出部31D亦可與踏力之值無關，將目標輔助力設定為0。 控制裝置30D亦可與控制裝置30A相同，具有2種控制模式。於第1控制模式中，控制裝置30D判斷車輛是否傾倒，於車輛傾倒之情形時，限制電動馬達21之驅動。於第2控制模式中，控制裝置30D不進行依據車體之左右方向之傾斜之電動馬達21之驅動之限制(於第1控制模式中執行之處理)。即，於第2控制模式中，控制裝置30D不將傾斜感測器53之輸出利用於電動馬達21之控制。控制裝置30D亦如圖5A所示，具有操作部46。控制裝置30D亦可根據自操作部46輸入之信號選擇性地執行第1控制模式與第2控制模式。藉由使用者進行之控制模式之選擇亦可未必成為可能。即，控制裝置30D亦可恆常性地執行第1控制模式中之控制。 於控制裝置30D具有2種控制模式之形態中，傾倒判定部36僅於經由操作部46選擇第1控制模式時執行。於選擇第2控制模式時，傾倒判定部36不執行，而是將藉由輔助力算出部31D算出之通常輔助力設定為目標輔助力。 圖5C係表示控制裝置30D執行之處理之一例之流程圖。控制裝置30D以特定之週期(例如，數十msec)重複執行該圖所示之處理。於控制裝置30D具有2種控制模式之形態中，該流程圖之處理係於選擇第1控制模式之情形時執行。 控制裝置30D基於轉矩感測器41之輸出信號而檢測施加至踏板2a之踏力，基於前輪旋轉感測器43之輸出信號而檢測車速(S401)。其次，輔助力算出部31D算出與踏力及車速相應之目標輔助力(S402)。 又，傾倒判定部36基於傾斜感測器53之輸出信號而檢測車體之向左右方向之傾斜角(S403)。而且，傾倒判定部36判斷車速是否小於閾值，並且判斷傾斜角是否大於傾倒判定閾值(S404、S405)。於車速小於閾值，且傾斜角大於傾倒判定閾值之情形時，控制裝置30D判斷為車輛傾倒，使電動馬達21之驅動停止(S406)。於S404中車速大於車速閾值之情形時，或於S405中車體之向左右方向之傾斜角小於傾倒判定閾值之情形時，馬達控制部32將與S402中算出之目標輔助力相應之指令值輸出至馬達驅動裝置39。 控制裝置30D執行之處理之流程並不限定於圖5C所示之例。例如，控制裝置30D亦可首先進行傾倒判定，算出目標輔助力。換言之，控制裝置30D亦可於進行S403、S404、S405之處理之後，算出目標輔助力。 [第5實施形態] 於第5實施形態中，踏力輔助系統具備用以檢測車體之姿勢變化之感測器。控制裝置基於車體之姿勢變化而判斷車輛之被盜，於檢測到車輛被盜之情形時驅動輸出警告之警告裝置。藉此，於對停車之車體發生被盜行為之情形時，使用者容易注意該情況。此處，車體之姿勢變化亦包含車體之振動。 圖6A係表示第5實施形態之電動輔助自行車1E、及電動輔助自行車1E所具備之踏力輔助系統之構成之方塊圖。圖6B係表示電動輔助自行車1E所具有之控制裝置30E之處理之方塊圖。於該等圖中，對與第1實施形態相同之裝置及功能，標註相同符號。以下，關於與第1實施形態相同之事項，省略其說明。 如圖6A所示，電動輔助自行車1E具有加速度感測器54，作為用以檢測車體之姿勢變化之感測器。加速度感測器54為1軸、2軸、或3軸之加速度感測器。加速度感測器54之加速度之檢測方向例如為車體之上下方向、前後方向、及左右方向中之任一個或複數個。例如，於後輪6上鎖之車輛中，存在於後輪6自路面上浮之狀態下被盜之情形。因此，於此種車輛之情形時，加速度感測器54之加速度之檢測方向例如為車體之前後方向或上下方向。又，存在於被盜時將設置於車體之上鎖機構破壞之情形。於此種情形時，存在車體於左右方向或前後方向大幅度振動之可能性。因此，亦可以加速度感測器54檢測車體之左右方向之加速度與前後方向之加速度之方式構成。 如圖6A所示，電動輔助自行車1E具有警告裝置38。警告裝置38例如為喇叭或顯示器、指示器等。警告裝置38根據自控制裝置30E輸入之信號，發出警告音，或顯示警告用訊息，或以預先決定之形態使發光部點亮。 如圖6B所示，控制裝置30E除了具有輔助力算出部31E與上述馬達控制部32以外，亦可具有被盜判定部37，作為其功能。被盜判定部37於車輛並非行駛中時，基於車體之姿勢變化(即基於由加速度感測器54檢測之加速度)而判斷車輛是否被盜。例如，被盜判定部37於檢測到大於閾值之加速度之情形時判斷為車輛被盜。又，於大於閾值之加速度較預先決定之時間長期繼續之情形時，被盜判定部37亦可判斷為車輛被盜。 作為進而其他例，於藉由加速度感測器54而檢測到之車體之振動符合預先決定之條件之情形時，被盜判定部37亦可判斷為車輛被盜。換言之，於藉由加速度感測器54檢測到之振動之振幅或方向、週期等為被盜時特有者之情形時，被盜判定部37亦可判斷為車輛被盜。例如，於具有大於閾值之振幅之振動較預先決定之時間長期繼續之情形時，被盜判定部37亦可判斷為車輛被盜。 作為進而其他例，電動輔助自行車1E亦可具有：上鎖機構，其設置於後輪6或前輪9；及開關，其檢測該上鎖機構之狀態(上鎖狀態/解鎖狀態)。於該情形時，被盜判定部37亦可基於開關之輸出信號而檢測上鎖機構之狀態。而且，例如於上鎖機構處於上鎖狀態，且檢測到上述車體之姿勢變化或振動時，被盜判定部37亦可判斷為車輛被盜。 控制裝置30E於藉由被盜判定部37而檢測到車輛被盜時，驅動警告裝置38輸出警告。具體而言，控制裝置30E發出警告音，或進行警告之顯示，或以預先決定之形態使發光部點亮。 再者，警告裝置38未必為搭載於電動輔助自行車1E之裝置。例如，警告裝置38亦可為使用者擁有之移動終端。於該情形時，電動輔助自行車1E包含無線通信裝置，控制裝置30E亦可經由通信裝置，而對使用者擁有之移動終端發送警告。 於第5實施形態中，於車輛之主開關(未圖示)處於關閉狀態，故而不容許自電池22向電動馬達21之電力供給之狀態之情形時，控制裝置30E亦藉由自電池22或控制裝置30E內置之電池接收之電力而執行上述被盜判定部37之處理。 輔助力算出部31E之處理與至此為止所說明之輔助力算出部31A～31D通常時進行之處理相同。即，輔助力算出部31E參照表示輔助力、踏力及車速之關係之映射表或關係式，算出與經檢測之踏力與車速相應之目標輔助力。 控制裝置30E亦可與控制裝置30A相同，具有2種控制模式。於第1控制模式中，控制裝置30E基於車體之姿勢變化而判斷車輛之被盜，於檢測到車輛被盜之情形時驅動輸出警告之警告裝置。於第2控制模式中，控制裝置30E不進行基於車體之姿勢變化之車輛之被盜判定。即，於第2控制模式中，控制裝置30E不將加速度感測器54之輸出利用於警告裝置38之驅動。控制裝置30E亦如圖6A所示，具有操作部46。控制裝置30E亦可根據自操作部46輸入之信號選擇性地執行第1控制模式與第2控制模式。藉由使用者進行之控制模式之選擇亦可未必成為可能。即，控制裝置30E亦可恆常性地執行第1控制模式中之控制。 於控制裝置30E具有2種控制模式之形態中，被盜判定部37僅於經由操作部46選擇第1控制模式時執行。於選擇第2控制模式時，被盜判定部37不執行。 圖6C係表示被盜判定部37執行之處理之一例之流程圖。被盜判定部37以特定之週期重複執行該圖所示之一系列之處理。於控制裝置30E具有2種控制模式之形態中，該流程圖之處理係於選擇第1控制模式之情形時執行。 被盜判定部37例如基於前輪旋轉感測器43之輸出信號，而檢測車速(S501)。又，被盜判定部37基於加速度感測器54之輸出信號，而檢測車體之加速度(車體之姿勢變化)(S502)。而且，被盜判定部37判斷車速是否低於閾值，即車輛是否並非行駛中(S503)。又，被盜判定部37判斷自S502中檢測到之加速度所獲得之車體之姿勢變化是否符合預先決定之條件，即姿勢變化是否為被盜時特有者(S504)。具體而言，例如判斷車體之姿勢變化(加速度)是否大於閾值，或車體之振動之振幅等是否符合預先決定之條件。於車速低於閾值，且自加速度所獲得之車體之姿勢變化符合預先決定之條件之情形時，控制裝置30E判斷為車輛被盜，驅動警告裝置38(S505)。另一方面，於車速高於閾值之情形時，或自加速度感測器54所獲得之車體之姿勢變化不符合預先決定之條件之情形時，結束此次之處理。 本發明並不限定於以上所說明之實施形態，可進行各種變更。 例如，控制裝置亦可具有上述控制裝置30A～30E之功能中複數個功能。例如，控制裝置亦可具有作為第1實施形態所說明之使加速順暢之功能，與作為第4實施形態所說明之檢測傾倒之功能。於該情形時，亦可於複數個功能中利用共用之加速度感測器。the following, One embodiment of the pedaling assisting system proposed in the present invention will be described with reference to the drawings. Fig. 1 is a side view of a power-assisted bicycle 1A as an example of the embodiment. Fig. 2A is a block diagram showing the configuration of the electric assist bicycle 1A of the first embodiment. The thick solid line in Figure 2A indicates the transmission of power, A thin solid line indicates a signal or current. The electric assist bicycle 1A has a pedal assisting system for assisting the rider's pedaling effort. The pedaling assist system is composed of the following electric motor 21, Control device 30A, Motor drive device 39, And power components such as sensors. [First Embodiment] As shown in Fig. 1, The electric assist bicycle 1A has a crank shaft 2. A pedal 2a is attached to both ends of the crankshaft 2. The crankshaft 2 is supported by the lower end of the seat tube 11. A seat portion 18 is fixed to the upper end of the seat tube 11. In front of the electric assisted bicycle 1A, The settings are: Handle column 8; Handle 7, It is fixed to the upper part of the handle post 8; Front fork 19, It is fixed to the lower part of the handle column 8; And the front wheel 9, It is supported by the lower end of the front fork 19. The handle post 8 is supported by a head pipe 17a provided at the front end of the frame 17. The power-assisted bicycle 1A has a drive unit 10 constituted by an electric motor 21 (refer to FIG. 2A) or a speed reducer 25 or the like for assisting a rider to apply a force (a pedaling force) to the pedal 2a. The electric motor 21 is driven by electric power supplied from the battery 22 (refer to FIG. 1). In the case of the electric assisted bicycle 1A, The battery 22 is mounted on the rear side of the seat tube 11, The drive unit 10 is disposed on the rear side of the crankshaft 2. The layout of the battery 22 and the drive unit 10 is not limited to the example of the electric assist bicycle 1A. It can be changed as appropriate. As shown in Figure 2A, The power (torque) applied to the crankshaft 2 via the pedal 2a is transmitted to the resultant force transmitting mechanism 24 via the one-way clutch 23. also, In the case of the electric assisted bicycle 1A, The power (assisted force) output from the electric motor 21 is transmitted to the resultant force transmitting mechanism 24 via the speed reducer 25 and the one-way clutch 26 . The resultant force transmitting mechanism 24 combines the power applied to the crankshaft 2 with the power output from the electric motor 21. The resultant force transmitting mechanism 24 is, for example, a shaft, a rotating member disposed on the shaft, Chain 5 (Fig. 1) and the like. In an example of the resultant force transmitting mechanism 24, The two powertrains are synthesized by input to a common shaft or a shared rotating member. As another example, Enter both of the two powers into the chain 5, And synthesize. The power synthesized by the resultant force transmitting mechanism 24 is as shown in FIG. 2A. It is transmitted to the rear wheel 6 via the shifting mechanism 27 and the one-way clutch 28, for example. The electric assist bicycle 1A may not have the shifting mechanism 27. The power-assisted bicycle 1A has a sensor for detecting the pedaling force applied by the rider to the pedal 2a. The sensor is shown in Figure 2A. For example, a torque sensor 41 that outputs a signal corresponding to the torque of the crankshaft 2. The torque sensor 41 is, for example, a magnetic strain type sensor provided on the crankshaft 2, However, the type thereof is not particularly limited. also, The electric assist bicycle 1A has: Motor rotation sensor (encoder) 42, a signal whose output corresponds to the rotational speed of the electric motor 21; Front wheel rotation sensor 43, a signal whose output corresponds to the rotational speed of the front wheel 9; And a crank rotation sensor 45, Its output corresponds to the signal of the rotational position of the crankshaft 2. The sensors 41, 42, 43. The output signal of 45 is input to the control device 30A that controls the electric motor 21. also, The power-assisted bicycle 1A has a user-operable operation portion 46. The operation unit 46 outputs a signal corresponding to the user's operation to the control device 30A. As described below, The control device 30A can also have two control modes. The first control mode is a mode in which the power (assist force) output from the electric motor 21 is lowered in an acceleration state in which the acceleration of the vehicle is higher than the threshold. The second control mode is a mode in which the reduction of the assist force (the process executed in the first control mode) is not performed in accordance with the comparison between the acceleration and the threshold. The control device 30A is based on the signal input from the operation unit 46, The first control mode and the second control mode are selectively executed. With this, The user can select two control modes. One example of the operation unit 46 is a display for displaying an option (first control mode/second control mode) provided to the user and a button for accepting selection by the user. As another example, The operation portion 46 may also be a button capable of performing an opening operation/closing operation. E.g, The first control mode can also be selected in the open state. The second control mode is executed in the off state. and then, The electric assist bicycle 1A has an acceleration sensor 51 for detecting the acceleration of the vehicle. The acceleration sensor 51 is provided in such a manner as to output a signal corresponding to the acceleration in the front and rear directions of the vehicle body. The control device 30A has: Memory, a program or mapping table that maintains control of the electric motor 21; And microprocessor, It executes the above program. The control device 30A detects the pedaling force of the rider based on the output of the torque sensor 41. The electric motor 21 is controlled such that the electric motor 21 outputs power (assisted force) corresponding to the pedaling force. The control device 30A outputs a command value corresponding to the pedaling force of the rider to the motor driving device 39. The motor driving device 39 receives the electric power of the battery 22 and supplies electric power corresponding to the command value to the electric motor 21. The motor drive unit 39 is constituted by, for example, a converter, an inverter, or the like. The control device 30A can also be in the control of the electric motor 21, The vehicle speed detected based on the output signal of the front wheel rotation sensor 43 is Or the rotational position or rotational speed of the crankshaft 2 detected based on the output signal of the crank rotation sensor 45. The control device 30A of the first embodiment is in an acceleration state in which the acceleration of the vehicle is higher than a threshold value. The power (assisted force) output from the electric motor 21 is reduced in comparison with the normal state in which the acceleration of the vehicle is less than the threshold. By this, Can suppress the unintended acceleration of the rider, Improves comfort during driving. The control device 30A may also select the first control mode only via the operation unit 46. Perform such control. Fig. 2B is a block diagram showing the processing of the control device 30A. As shown in the figure, The control device 30A has the assisting force calculating unit 31A, Motor control unit 32, And acceleration determination unit 33, As its function. These functions are realized by the microprocessor executing a program stored in the memory of the control device 30A. The acceleration determination unit 33 determines whether or not the vehicle is rapidly accelerating. in particular, The acceleration determination unit 33 determines whether the acceleration of the vehicle is higher than a threshold value, When the acceleration of the vehicle is higher than the threshold, it is determined that the vehicle is in an acceleration state (this threshold is referred to as an "acceleration determination threshold"). also, The acceleration determination unit 33 determines that the vehicle is in the normal state when the acceleration of the vehicle is lower than the acceleration determination threshold. The acceleration determination unit 33 detects the acceleration of the vehicle based on, for example, the output signal of the acceleration sensor 51. The acceleration determination unit 33 can also replace the output signal of the acceleration sensor 51. The acceleration of the vehicle is calculated based on the output signal of the front wheel rotation sensor 43. The acceleration determination unit 33 is as shown in FIG. 2B. The threshold value setting unit 33a that changes the acceleration determination threshold value in accordance with the operating state of the vehicle may be provided. and, The acceleration determination unit 33 can also determine whether or not the acceleration of the vehicle is higher than the acceleration determination threshold set by the threshold setting unit 33a. The operating state used by the threshold setting unit 33a for setting the threshold includes the vehicle speed, Or the pedaling force applied to the pedal 2a or the like. E.g, If the speed of the car goes high, Then, the threshold setting unit 33a lowers the threshold. Control device 30A can also detect the output voltage of battery 22. In this case, The threshold setting unit 33a can also set a threshold based on the output voltage of the battery 22. E.g, The threshold setting unit 33a may also be in the case where the output voltage of the battery 22 drops. Decrease the threshold. By this, It is possible to effectively suppress the electric motor 21 from being driven during the sudden acceleration in the state where the output voltage of the battery 22 is lowered. Furthermore, As another example, The threshold value may be, for example, a predetermined fixed value. The assist force calculation unit 31A calculates the power (assist force) to be output by the electric motor 21, That is the target assist force. The assist force calculation unit 31A calculates a target assist force corresponding to the pedaling force and the vehicle speed applied to the pedal 2a. E.g, The assisting force calculating unit 31A refers to the assisting force, a mapping table or relationship between the pedaling force and the speed of the vehicle, Calculate the assist force corresponding to the pedaling force and the vehicle speed detected by the sensor (hereinafter, This assisting force is referred to as a normal assisting force). In one example of a power-assisted bicycle, The assist rate (assistance rate = assist force / pedaling force) is stored in advance in the memory in accordance with the vehicle speed. The assisting force calculating unit 31A multiplies the assisting rate corresponding to the vehicle speed detected by the sensor by the pedaling force, The result of multiplication is set as the usual assisting force. In the first embodiment, When it is determined that the vehicle is not in the acceleration state as a result of the processing of the acceleration determination unit 33, That is, when the vehicle is in the normal state, The control device 30A sets the normal assisting force as the target assisting force. The assist force calculating unit 31A is as shown in FIG. 2B. The assisting force reducing unit 31a is included. When the vehicle is in an acceleration state, the assisting force reducing portion 31a The assist force lower than the usual assist force is set as the target assist force. E.g, The assisting force reducing portion 31a multiplies the normal assisting force by a coefficient (for example, Coefficient <1), The result of multiplication is set as the target assist force. As another example, It is also possible to set the assist rate set according to the vehicle speed and the coefficient for reducing the assist force (for example, Coefficient <1) multiplied by the pedaling force, The result of multiplication is set as the target assist force. In still other examples, The assisting force reducing portion 31a may also subtract a fixed value from the normal assisting force. The result of the subtraction is set as the target assist force. As still another example, The assisting force reducing portion 31a may also be when the vehicle is in an accelerated state. The reference indicates an assist force lower than the usual assist force, Stepping force, a mapping table or relationship between the speed and speed, The assist force obtained from the mapping table or relationship is set as the target assist force. This map or relational expression is also stored, for example, in advance in the memory of the control device 30A. As still another example, The assisting force reducing unit 31a may also set the assisting force lower than the minimum value of the target assisting force that can be set in the normal state as the target assisting force. E.g, The assisting force reducing unit 31a may also set 0 as the target assisting force. The motor control unit 32 outputs a command value corresponding to the target assist force calculated by the processing of the assist force calculating unit 31A to the motor drive device 39. also, The motor control unit 32 calculates the rotational speed of the electric motor 21 based on the output signal of the motor rotation sensor 42. It is also monitored whether or not the electric motor 21 is properly driven in accordance with the command value. Furthermore, In the form in which the control device 30A has two control modes, The acceleration determination unit 33 and the assist force reduction unit 31a are executed only when the first control mode is selected via the operation unit 46. When selecting the second control mode, The acceleration determination unit 33 and the assist force reduction unit 31a are not executed. Instead, the normal assist force calculated by the assist force calculating unit 31A is set as the target assist force. which is, The control device 30A is in the second control mode, The output of the acceleration sensor 51 is not utilized for the calculation of the target assist force. The choice of control mode by the user may not be possible. which is, The control device 30A can also constantly perform the control in the first control mode. Fig. 2C is a flow chart showing an example of processing executed by the control device 30A. The control device 30A is in a specific cycle (for example, Dozens of msec) Repeat the processing shown in the figure. In the form in which the control device 30A has two control modes, The processing of this flowchart is executed when the first control mode is selected. The control device 30A detects the pedaling force applied to the pedal 2a based on the output signal of the torque sensor 41, The vehicle speed is detected based on the output signal of the front wheel rotation sensor 43 (S101). Secondly, The assist force calculation unit 31A calculates a normal assist force corresponding to the detected pedal effort and the vehicle speed (S102). also, The acceleration determination unit 33 detects the acceleration of the vehicle based on the output signal of the acceleration sensor 51 (or the front wheel rotation sensor 43) (S103), It is also determined whether the detected acceleration is greater than the acceleration determination threshold (S104). The acceleration determination threshold used in the process of S104 is, for example, by the threshold setting unit 33a. The threshold value set according to the operating state of the vehicle. When the acceleration is higher than the acceleration determination threshold, That is, when the vehicle is in an accelerated state, By the processing of the assisting force reducing unit 31a, On the other hand, the assisting force lower than the normal assisting force calculated in S102 is set as the target assisting force (S105). on the other hand, When the acceleration is not higher than the acceleration determination threshold, That is, when the vehicle is in the normal state, The normal assist force calculated by the assist force calculating unit 31A in S102 is the target assist force (S106). then, The motor control unit 32 outputs a command value corresponding to the target assist force calculated in S105 or S106 to the motor drive unit 39 (S107). The above is an example of the processing executed by the control device 30A. Furthermore, The threshold setting unit 33a may also make the acceleration determination threshold used in the acceleration state different from the acceleration determination threshold used in the normal state. E.g, The threshold used in the acceleration state may also be lower than the acceleration determination threshold used in the normal state. By this, The determination result of S104 can be frequently switched when the acceleration of the vehicle is close to the threshold value. E.g, It is also possible to use the first value as the acceleration determination threshold when it is determined that the vehicle is in the normal state in the processing before one cycle. When it is judged that the vehicle is in an accelerated state in the processing before one cycle, The second threshold lower than the first value is used as the acceleration determination threshold. It can also replace the example shown in Figure 2C. When the vehicle returns from the acceleration state to the normal state, the assist force calculation unit 31A The target assist force is gradually approached to the usual assist force. E.g, When the vehicle returns from the acceleration state to the normal state, the assist force calculation unit 31A Multiply the usual assist or assist rate by the factor, The result of multiplication is set as the target assist force. at this time, It is also possible to gradually bring the coefficient closer to 1 from a value less than one. By this, Can be suppressed when the vehicle returns from the accelerated state to the normal state, The assist force suddenly rose. The process when the vehicle returns from the acceleration state to the normal state is not limited to this. E.g, The assist force calculation unit 31A may return to the normal state when the vehicle returns from the acceleration state. The setting of the usual assisting force as the target assisting force is started again directly. The control device 30A may not have the acceleration determination unit 33. which is, The assist force calculating unit 31A may also replace S104 shown in FIG. 2C. S105, S106 processing, The coefficient set according to the acceleration of the vehicle is multiplied by the usual assist force or assist rate. The coefficient is stored in advance in the memory corresponding to the acceleration of the vehicle. For example, it is continuously specified in accordance with the acceleration of the vehicle. also, This coefficient is specified in such a way that the assisting force with respect to a relatively higher acceleration is less than the assisting force with respect to a relatively low acceleration. which is, This coefficient is defined in such a manner that the coefficient with respect to the relatively high acceleration (the coefficient in the acceleration state) is smaller than the coefficient with respect to the relatively low acceleration (the coefficient in the normal state). If such a coefficient is used, Then the judgment of S104 may not be performed. In the accelerated state, the assist force is lowered compared to the normal state. also, The assist force can be continuously changed according to the change in acceleration. With this, Can improve the ride feel of the vehicle. [Second Embodiment] The control device according to the second embodiment determines whether or not the rear wheel 6 is slipping by the acceleration of the vehicle. and, The control device is in a state where the rear wheel 6 is slipping, The assisting force output from the electric motor 21 is reduced as compared with the normal state in which no slip occurs. By this, It can improve the acceleration or comfort on the road surface with low friction coefficient such as gravel road or mud road. Fig. 3A shows a power-assisted bicycle 1B according to a second embodiment, And a block diagram of the structure of the pedaling assist system provided by the electric assist bicycle 1B. Fig. 3B is a block diagram showing the processing of the control device 30B provided in the power-assisted bicycle 1B. In the figures, The same symbols and functions as those of the first embodiment are denoted by the same reference numerals. the following, The same matters as in the first embodiment are The description is omitted. As shown in Figure 3A, The power-assisted bicycle 1B has a signal that outputs a rotation speed corresponding to the rotational speed of the rear wheel 6, and then rotates the sensor 44. also, The electric assist bicycle 1B has the above-described acceleration sensor 51. The acceleration sensor 51 is the same as that described in the first embodiment. The signal corresponding to the acceleration in the front and rear directions of the vehicle body is output. As shown in Figure 3B, The control device 30B has the assisting force calculating unit 31B, The motor control unit 32, And the slip determination unit 34, As its function. These functions are realized by the microprocessor executing a program stored in the memory of the control device 30B. When the rear wheel 6 is slipping, The rotational acceleration of the rear wheel 6 is larger than the acceleration of the vehicle. therefore, The slip determination unit 34 calculates the rotational acceleration of the rear wheel 6 and the actual acceleration of the vehicle based on the output signal of the rear wheel rotation sensor 44. It is judged whether or not the rear wheel 6 is slipping. E.g, The acceleration of the slip determination unit 34 in the vehicle is less than the first threshold. On the other hand, when the rotational acceleration of the rear wheel 6 is greater than the second threshold, It is judged that the rear wheel 6 is slipping. The slip determination unit 34 detects the actual acceleration of the vehicle based on, for example, the output signal of the acceleration sensor 51. Can also replace it, The slip determination unit 34 is based on the output signal of the front wheel rotation sensor 43. The actual acceleration of the vehicle is detected. As another example, The slip determination unit 34 can also be based on the sensor 51, The dimension of the acceleration of the detected vehicle of the output of 43 and the dimension of the rotational acceleration of the rear wheel 6 detected based on the output of the rear wheel rotation sensor 44 are unified by the diameter of the rear wheel 6, The dimensions are compared by two uniform accelerations. which is, The slip determination unit 34 calculates the self-sensor 51 using the diameter (r) of the rear wheel 6, The actual acceleration (dv/dt) of the vehicle obtained by the output signal of 43 corresponds to the rotational acceleration (dω/dt) of the rear wheel 6 (dω/dt=(dv/dt)/r). and, It is also possible to compare the rotational acceleration of the rear wheel 6 with the actual acceleration of the vehicle and the rotational acceleration of the rear wheel 6 obtained from the force of the rear wheel rotation sensor 44. then, When the difference between the two rotational accelerations is greater than the threshold, The slip determination unit 34 can also determine that the rear wheel 6 is slipping. As still another example, The slip determination unit 34 can also calculate the acceleration of the vehicle based on the output of the rear wheel rotation sensor 44 and the diameter of the rear wheel 6. And the acceleration and self-sensor 51 obtained from the output of the rear wheel rotation sensor 44, The acceleration obtained by the output signal of 43 is compared. and, When the difference is greater than the threshold, The slip determination unit 34 can also determine that the rear wheel 6 is slipping. Similar to the first embodiment, The threshold value used by the slip determining unit 34 can also be changed in accordance with the operating state of the vehicle. Here, The operating state includes, for example, the vehicle speed. E.g, If the speed of the car goes high, Then, the slip determination unit 34 lowers the threshold. The assist force calculation unit 31B is the same as the first embodiment. The assisting force corresponding to the pedaling force and the vehicle speed applied to the pedal 2a is calculated. E.g, The assisting force calculating unit 31B refers to the assisting force, a mapping table or relationship between the pedaling force and the speed of the vehicle, Calculate the usual assist force corresponding to the detected pedaling force and vehicle speed. In one case, The assisting force calculation unit 31B multiplies the coefficient set according to the vehicle speed by the pedaling force. The result of multiplication is set as the usual assisting force. When the vehicle is in the normal state (that is, the state in which the rear wheel 6 is not slipped), the assisting force calculation unit 31B The usual assist force is set as the target assist force. The assist force calculation unit 31B includes an assist force reduction unit 31b. When the assisting force reducing portion 31b is slipping on the rear wheel 6, The assist force lower than the usual assist force is set as the target assist force. E.g, The assisting force reducing portion 31b multiplies the normal assisting force by a coefficient (for example, Coefficient <1), The result of multiplication is set as the target assist force. As another example, The assisting force reducing unit 31b may also use the coefficient for reducing the assist ratio and the assisting force set according to the vehicle speed (for example, Coefficient <1) multiplied by the pedaling force, The result of multiplication is set as the target assist force. As still another example, The assisting force reducing portion 31b can also subtract a fixed value from the normal assisting force. The result of the subtraction is set as the target assist force. As still another example, The assisting force reducing unit 31b can also refer to an assisting force indicating that it is lower than the normal assisting force, The pedaling force applied to the pedal 2a, a mapping table or relationship between the speed and speed, The assist force obtained from the mapping table or relationship is set as the target assist force. The assisting force reducing unit 31b can also set 0 as the target assisting force. In other words, When the assisting force reducing portion 31b generates the slip of the rear wheel 6, The driving of the electric motor 21 can also be stopped. The control device 30B is also the same as the control device 30A. There are 2 control modes. In the first control mode, The control device 30B determines whether the rear wheel 6 is slipping, The assisting force output from the electric motor 21 is lowered in a state where the rear wheel 6 is slipped. In the second control mode, The control device 30B does not perform the reduction of the assisting force (the processing executed in the first control mode) in accordance with the slip determination of the rear wheel 6. which is, The control device 30B is in the second control mode, The output of the acceleration sensor 51 is not utilized for the calculation of the target assist force. As shown in Figure 3A, The control device 30B is also the same as the control device 30A. There is an operation unit 46. The control device 30B can also selectively execute the first control mode and the second control mode based on the signal input from the operation unit 46. The choice of control mode by the user may not be possible. which is, The control device 30B can also constantly perform the control in the first control mode. In the form in which the control device 30B has two control modes, The slip determination unit 34 and the assist force reduction unit 31b are executed only when the first control mode is selected via the operation unit 46. When selecting the second control mode, The slip determination unit 34 and the assist force reduction unit 31b are not executed. Instead, the normal assist force calculated by the assist force calculating unit 31B is set as the target assist force. Fig. 3C is a flow chart showing an example of processing executed by the control device 30B. The control device 30B is in a specific cycle (for example, Dozens of msec) Repeat the processing of one of the series shown in the figure. In the form in which the control device 30B has two control modes, The processing of this flowchart is executed when the first control mode is selected. The control device 30B detects the pedaling force applied to the pedal 2a based on the output signal of the torque sensor 41, The vehicle speed is detected based on the output signal of the front wheel rotation sensor 43 (S201). Secondly, The assist force calculation unit 31B calculates a normal assist force corresponding to the pedal effort and the vehicle speed (S202). also, The slip determination unit 34 detects the acceleration of the vehicle based on the output signal of the acceleration sensor 51 (or the front wheel rotation sensor 43) (S203). also, The slip determination unit 34 calculates the rotational acceleration of the rear wheel 6 based on the output signal of the rear wheel rotation sensor 44 (S204). and, The slip determination unit 34 calculates the acceleration of the rear wheel 6 and the acceleration calculated based on the output signal of the acceleration sensor 51 (or the front wheel rotation sensor 43) based on the output signal of the rear wheel rotation sensor 44. It is judged whether or not the rear wheel 6 is slipping (S205). When the rear wheel 6 is slipping, The assisting force reducing unit 31b sets the assisting force lower than the normal assisting force as the target assisting force (S206). on the other hand, When the slip of the rear wheel 6 is not generated, The assist force calculation unit 31B sets the normal assist force calculated in S202 as the target assist force (S208). then, The motor control unit 32 outputs a command value corresponding to the target assist force to the motor drive unit 39 (S207). In an example of the processing of the control device 30B, The assist force calculation unit 31B is the same as the assist force calculation unit 31A. When returning to the normal state from the state in which the rear wheel 6 is slipping, It is also possible to gradually bring the target assisting force closer to the usual assisting force. E.g, The assist force calculation unit 31B multiplies the normal assist force by a coefficient, The result of multiplication is set as the target assist force. at this time, The assist force calculating unit 31B can also make the coefficient gradually approach 1 from a value lower than 1. The process from when the state in which the rear wheel 6 is slipped back to the normal state is not limited to this. E.g, When the assist force calculation unit 31B returns to the normal state, The process of setting the usual assist force as the target assist force is started again directly. [Third embodiment] In the third embodiment, The pedal assist system has a tilt sensor for detecting that the vehicle is traveling on a ramp. As an acceleration sensor. The tilt sensor is specifically a sensor that detects a pitch angle of a vehicle body (an inclination angle of a vehicle body centered on an axis in the left-right direction of the vehicle body). When the vehicle is driving on a ramp, Compared to when the vehicle is driving on a flat road, The assist force output from the electric motor 21 is increased, Or lower. By this, When the vehicle is driving uphill, for example, Can automatically obtain a larger auxiliary force, Comfortable driving, also, Can be restrained when the vehicle is driving downhill, Unnecessary power consumption. Fig. 4A is a view showing a power-assisted bicycle 1C according to a third embodiment; And a block diagram of the structure of the pedaling assist system provided by the electric assist bicycle 1C. Fig. 4B is a block diagram showing the processing of the control device 30C of the power-assisted bicycle 1C. In the figures, The same devices and functions as those of the first embodiment are Label the same symbol. the following, The same matters as in the first embodiment are The description is omitted. As shown in Figure 4A, The power-assisted bicycle 1C has a tilt sensor 52. As the tilt sensor 52, 1 axis is available, 2 axes, Or 3-axis acceleration sensor. The detection direction of the acceleration of the tilt sensor 52 is set such that the output signal of the tilt sensor 52 changes according to the pitch angle of the vehicle body. E.g, The detection direction of the acceleration of the tilt sensor 52 is the front and rear direction of the vehicle body. When the detection direction is set to the direction, For example, when the vehicle is uphill, The acceleration (gravity) of the vehicle body detected by the tilt sensor 52 increases. The detection direction of the acceleration of the tilt sensor 52 may also be the front and rear direction of the vehicle body and the left and right direction of the vehicle body. and then, The detection direction of the acceleration of the tilt sensor 52 may also be the left and right direction and the up and down direction of the vehicle body. As shown in Figure 4B, The control device 30C has an assist force calculating unit 31C, The motor control unit 32, And a slope determination unit 35, As its function. These functions are realized by the microprocessor executing a program stored in the memory of the control device 30C. The ramp determination unit 35 calculates the pitch angle of the vehicle body based on the output signal of the tilt sensor 52. which is, The ramp determination unit 35 calculates the pitch angle of the vehicle body based on the acceleration (gravity) of the vehicle body detected by the tilt sensor 52. and, The ramp determination unit 35 determines whether or not the vehicle is traveling on a slope based on the calculated pitch angle. More specifically, The slope determination unit 35 determines whether or not the vehicle is traveling uphill based on the pitch angle. E.g, When the sign of the pitch angle when the vehicle body is tilted in such a manner that the front portion of the vehicle body is raised is set to be positive, When the pitch angle is greater than the threshold (threshold value > 0), the ramp determination unit 35 It is determined that the vehicle is traveling on a slope (hereinafter, the threshold is referred to as an uphill determination threshold). also, The slope determination unit 35 can also determine whether the vehicle is traveling downhill based on the pitch angle. E.g, When the sign of the pitch angle when the vehicle body is tilted in such a manner that the rear portion of the vehicle body is raised is set to be negative, When the calculated pitch angle is smaller than the threshold (threshold value < 0), the slope determination unit 35 It can also be determined that the vehicle is traveling downhill (hereinafter, the threshold is referred to as a downhill determination threshold). The assist force calculation unit 31C is the same as the assist force calculation unit 31A of the first embodiment. The assisting force corresponding to the pedaling force and the vehicle speed applied to the pedal 2a is calculated. E.g, The assisting force calculation unit 31C refers to the assist force, a mapping table or relationship between the pedaling force and the speed of the vehicle, Calculate the usual assist force corresponding to the detected pedaling force and vehicle speed. In one case, The assisting force calculation unit 31C multiplies the assist rate set according to the vehicle speed by the pedaling force. The result of multiplication is set as the usual assisting force. When the vehicle is not traveling uphill or downhill, the assisting force calculation unit 31C In other words, when the vehicle is driving on a flat road, The usual assist force is set as the target assist force. The assist force calculation unit 31C includes an assist force increasing unit 31c that increases the assist force when the vehicle travels uphill. When the vehicle is traveling uphill, the assisting force increasing portion 31c The electric motor 21 is controlled such that the electric motor 21 outputs an assist force greater than a normal assisting force. E.g, The assisting force increasing portion 31c multiplies the normal assisting force by a coefficient (for example, Coefficient >1), The result of multiplication is set as the target assist force. As another example, The assisting force calculation unit 31C may also set an assist ratio and a coefficient set according to the vehicle speed (for example, Coefficient >1) multiplied by the pedaling force, The result of multiplication is set as the target assist force. As still another example, The assisting force increasing portion 31c may also add a normal assisting force to a fixed value. The result of the addition is set as the target assist force. As still another example, The mapping table or relationship for uphill can also be stored in advance in the memory. In the mapping table or relationship, Indicates that there is an assist force higher than the usual assist force, Stepping force, And the relationship between speed, The assisting force increasing unit 31c can also calculate the target assisting force by referring to the map or the relational expression. The target assisting force calculated by the assisting force increasing portion 31c can also be based on the inclination of the uphill slope. That is, it becomes larger according to the pitch angle of the vehicle body. E.g, The coefficient used by the assisting force increasing unit 31c is increased in accordance with the pitch angle of the vehicle body. By this, That is, when it is convenient to drive on steep slopes, Can also travel smoothly, Improves comfort during driving. The coefficient is not limited to this, It can also be a fixed value. The assisting force calculating unit 31C includes an assisting force reducing unit 31d that reduces the assisting force when the vehicle travels downhill. When the vehicle is traveling downhill, the assisting force reducing unit 31d The electric motor 21 is controlled such that the assisting force output by the electric motor 21 is smaller than the normal assisting force. In one case, The assisting force reducing unit 31d can also stop the driving of the electric motor 21. E.g, The assist force reducing unit 31d can also stop the supply of electric power from the motor driving device 39 to the electric motor 21. The assisting force reducing portion 31d can also set the assisting force lower than the normal assisting force as the target assisting force. E.g, The assisting force reducing portion 31d may also multiply the normal assisting force by a coefficient (for example, Coefficient <1), The result of multiplication is set as the target assist force. As another example, The assisting force reducing unit 31d can also set the assist ratio and the coefficient according to the vehicle speed (for example, Coefficient <1) multiplied by the pedaling force, The result of multiplication is set as the target assist force. As still another example, The assisting force reducing portion 31d can also subtract a fixed value from the normal assisting force. The result of the subtraction is set as the target assist force. As still another example, The mapping table or relationship for downhill can also be stored in advance in the memory. In the mapping table or relationship, Indicates that there is an assist force lower than the usual assist force, Stepping force, And the relationship between speed, The assisting force reducing unit 31d can also calculate the target assisting force by referring to the map or the relational expression. The assisting force reducing unit 31d can also set 0 as the target assisting force. The target assisting force calculated by the assisting force reducing unit 31d can also be based on the inclination of the downhill slope. That is, it becomes smaller according to the pitch angle of the vehicle body. E.g, The coefficient used by the assisting force reducing unit 31d becomes smaller in accordance with the pitch angle (ie, The coefficient is close to 0). The coefficient is not limited to this, It can also be a fixed value. The control device 30C is also the same as the control device 30A. There are 2 control modes. In the first control mode, The control device 30C determines whether the vehicle is traveling on a ramp, When the vehicle is driving on a ramp, The assist force output from the electric motor 21 is increased, Or lower. In the second control mode, The control device 30C does not perform the increase/decrease of the assisting force according to the inclination of the road (the processing executed in the first control mode). which is, The control device 30C is in the second control mode, The output of the tilt sensor 52 is not utilized for the calculation of the target assist force. Control device 30C is also shown in Figure 4A. There is an operation unit 46. The control device 30C can also selectively execute the first control mode and the second control mode based on the signal input from the operation unit 46. The choice of control mode by the user may not be possible. which is, The control device 30C can also constantly perform the control in the first control mode. In the form in which the control device 30C has two control modes, Hill determination unit 35, The assist force increasing unit 31c and the assist force reducing unit 31d are executed only when the first control mode is selected via the operation unit 46. When selecting the second control mode, The processing of the hill determining unit 35 and the assisting force increasing unit 31c and the assisting force reducing unit 31d are not executed. The normal assist force calculated by the assist force calculating unit 31C is set as the target assist force. Fig. 4C is a flow chart showing an example of processing executed by the control device 30C. The control device 30C is in a specific cycle (for example, Dozens of msec) Repeat the processing of one of the series shown in the figure. In the form in which the control device 30C has two control modes, The processing of this flowchart is executed when the first control mode is selected. The control device 30C detects the pedaling force applied to the pedal 2a based on the output signal of the torque sensor 41, The vehicle speed is detected based on the output signal of the front wheel rotation sensor 43 (S301). Secondly, The assist force calculation unit 31C calculates a normal assist force corresponding to the pedaling force and the vehicle speed (S302). also, The ramp determination unit 35 detects the pitch angle based on the output signal of the tilt sensor 52 (S303). and, The ramp determination unit 35 determines whether or not the pitch angle is larger than the uphill determination threshold (S304). Here, When the pitch angle is greater than the uphill determination threshold, That is, when the vehicle is driving uphill, The assisting force increasing portion 31c increases the assisting force. in particular, The assisting force increasing portion 31c sets the assisting force higher than the normal assisting force as the target assisting force (S305). E.g, The assist rate and coefficient that will be set according to the speed of the vehicle (for example, Coefficient >1) multiplied by the pedaling force, The result of multiplication is set as the target assist force. When the pitch angle is not greater than the uphill determination threshold, The slope determination unit 35 determines whether or not the pitch angle is smaller than the downhill determination threshold (S307). When the pitch angle is less than the downhill determination threshold, That is, when the vehicle is driving downhill, The assisting force reducing unit 31d stops the driving of the electric motor 21 (S308). When the pitch angle is not less than the downhill determination threshold, The assist force calculation unit 31C sets the normal assist force as the target assist force (S309). The motor control unit 32 outputs a command value corresponding to the set target assist force to the motor drive unit 39 (S306). Furthermore, The control device 30C does not necessarily have the ramp determination unit 35. In this case, A relationship or a map indicating a relationship between a pitch angle and a coefficient may be stored in advance in the memory. The assist force calculating unit 31C uses a coefficient corresponding to the detected pitch angle, Increase the usual assistive force, Or reduce the usual assistive force. [Fourth embodiment] In the fourth embodiment, The pedal assist system is provided with a sensor for detecting the tilt of the vehicle body in the right and left direction. and, The control device detects the dumping of the vehicle body based on the inclination of the vehicle body. The driving of the electric motor 21 is restricted when the dumping of the vehicle body is detected. By this, Can be suppressed in the state where the vehicle is dumped, Unnecessarily consumes electricity. Fig. 5A is a view showing a power-assisted bicycle 1D according to a fourth embodiment, And a block diagram of the structure of the pedaling assist system provided by the electric assist bicycle 1D. Fig. 5B is a block diagram showing the processing of the control device 30D of the power-assisted bicycle 1D. In the figures, The same devices and functions as those of the first embodiment are Label the same symbol. the following, The same matters as in the first embodiment are The description is omitted. As shown in Figure 5A, The power-assisted bicycle 1D has a tilt sensor 53. As the tilt sensor 53, 1 axis is available, 2 axes, Or 3-axis acceleration sensor. The detection direction of the acceleration of the tilt sensor 53 is set such that the output signal of the tilt sensor 53 changes in accordance with the tilt of the vehicle body in the left-right direction (ie, the roll angle). E.g, The detection direction of the acceleration of the tilt sensor 52 is the left and right direction of the vehicle body. The detection direction of the acceleration of the tilt sensor 52 is in addition to the left and right direction of the vehicle body. It can also include the front and rear direction or the up and down direction. As shown in Figure 5B, The control device 30D has the assisting force calculating unit 31D, The motor control unit 32, And the dump determination unit 36, As its function. These functions are also implemented by the microprocessor executing a program stored in the memory of the control device 30D. The tilt determination unit 36 detects the tilt angle (roll angle) of the vehicle body in the left-right direction based on the output signal of the tilt sensor 53. The dump determination unit 36 determines whether or not the vehicle is tilted based on the tilt angle. E.g, When the tilt angle is greater than the threshold value, the dump determination unit 36 It is determined that the vehicle is tilted (hereinafter, the threshold is referred to as a dump determination threshold). The dump determination unit 36 can also determine whether or not the vehicle is tilted based on the inclination angle of the vehicle body and the vehicle speed. E.g, The dump determination unit 36 may also be when the vehicle speed is lower than the threshold and the tilt angle is greater than the dump determination threshold. It is judged that the vehicle is dumped. The control device 30D limits the driving of the electric motor 21 when detecting that the vehicle body is tilted. in particular, The control device 30D stops the driving of the electric motor 21 when detecting that the vehicle body is tilted. in particular, The motor control unit 32 stops the output of the command value to the motor drive unit 39. Alternatively, the supply of electric power from the motor driving device 39 to the electric motor 21 is stopped. The assist force calculation unit 31D is the same as the assist force calculation unit 31A of the first embodiment. The assisting force corresponding to the pedaling force and the vehicle speed applied to the pedal 2a is calculated. E.g, The assisting force calculating unit 31D refers to the assisting force, a mapping table or relationship between the pedaling force and the speed of the vehicle, Calculate the target assist force corresponding to the detected pedaling force and vehicle speed. In one case, The assisting force calculation unit 31D multiplies the assist rate set according to the vehicle speed by the pedaling force. The result of multiplication is set as the target assist force. The result of the processing by the dump determination unit 36, When detecting the dumping of the car body, The assist force calculating unit 31D may be independent of the value of the pedaling force. Set the target assist force to 0. The control device 30D can also be the same as the control device 30A. There are 2 control modes. In the first control mode, The control device 30D determines whether the vehicle is dumped, When the vehicle is dumped, The driving of the electric motor 21 is restricted. In the second control mode, The control device 30D does not perform the restriction of the driving of the electric motor 21 in accordance with the inclination of the left and right direction of the vehicle body (the processing executed in the first control mode). which is, In the second control mode, The control device 30D does not utilize the output of the tilt sensor 53 for the control of the electric motor 21. Control device 30D is also shown in Figure 5A. There is an operation unit 46. The control device 30D can also selectively execute the first control mode and the second control mode based on the signal input from the operation unit 46. The choice of control mode by the user may not be possible. which is, The control device 30D can also constantly perform the control in the first control mode. In the form in which the control device 30D has two control modes, The dump determination unit 36 is executed only when the first control mode is selected via the operation unit 46. When selecting the second control mode, The dump determination unit 36 does not execute, Instead, the normal assist force calculated by the assist force calculating unit 31D is set as the target assist force. Fig. 5C is a flow chart showing an example of processing executed by the control device 30D. The control device 30D is in a specific cycle (for example, Dozens of msec) Repeat the processing shown in the figure. In the form in which the control device 30D has two control modes, The processing of this flowchart is executed when the first control mode is selected. The control device 30D detects the pedaling force applied to the pedal 2a based on the output signal of the torque sensor 41, The vehicle speed is detected based on the output signal of the front wheel rotation sensor 43 (S401). Secondly, The assist force calculation unit 31D calculates the target assist force corresponding to the pedaling force and the vehicle speed (S402). also, The dump determination unit 36 detects the tilt angle of the vehicle body in the left-right direction based on the output signal of the tilt sensor 53 (S403). and, The dump determination unit 36 determines whether the vehicle speed is less than a threshold value, And determining whether the tilt angle is greater than a dumping determination threshold (S404, S405). The vehicle speed is less than the threshold, And when the tilt angle is greater than the dumping determination threshold, The control device 30D determines that the vehicle is dumped, The driving of the electric motor 21 is stopped (S406). When the vehicle speed is greater than the vehicle speed threshold in S404, Or in S405, when the inclination angle of the vehicle body in the left-right direction is smaller than the dumping determination threshold, The motor control unit 32 outputs a command value corresponding to the target assist force calculated in S402 to the motor drive unit 39. The flow of the processing executed by the control device 30D is not limited to the example shown in FIG. 5C. E.g, The control device 30D may also perform the dumping determination first. Calculate the target assist force. In other words, The control device 30D can also perform S403, S404, After the processing of S405, Calculate the target assist force. [Fifth Embodiment] In the fifth embodiment, The pedal assist system is provided with a sensor for detecting a change in posture of the vehicle body. The control device determines that the vehicle is stolen based on the change in the posture of the vehicle body. A warning device that outputs a warning is detected when a situation in which the vehicle is stolen is detected. With this, In the case of theft of the parking body, Users are easy to pay attention to this situation. Here, The posture change of the car body also includes the vibration of the car body. Fig. 6A is a view showing a power-assisted bicycle 1E according to a fifth embodiment, And a block diagram of the structure of the pedaling assist system provided by the electric assist bicycle 1E. Fig. 6B is a block diagram showing the processing of the control device 30E of the power-assisted bicycle 1E. In the figures, The same devices and functions as those of the first embodiment are Label the same symbol. the following, The same matters as in the first embodiment are The description is omitted. As shown in Figure 6A, The electric assist bicycle 1E has an acceleration sensor 54, As a sensor for detecting a change in posture of a vehicle body. The acceleration sensor 54 is 1 axis, 2 axes, Or 3-axis acceleration sensor. The detection direction of the acceleration of the acceleration sensor 54 is, for example, the upper and lower directions of the vehicle body, Front and rear direction, And one or more of the left and right directions. E.g, In the vehicle locked to the rear wheel 6, It exists in the case where the rear wheel 6 is stolen from the road surface. therefore, In the case of such a vehicle, The detection direction of the acceleration of the acceleration sensor 54 is, for example, a front-rear direction or an up-and-down direction of the vehicle body. also, It exists in the case where the lock mechanism is placed on the vehicle body when it is stolen. In this case, There is a possibility that the vehicle body vibrates greatly in the left-right direction or the front-rear direction. therefore, The acceleration sensor 54 may be configured to detect the acceleration of the vehicle body in the left-right direction and the acceleration in the front-rear direction. As shown in Figure 6A, The electric assist bicycle 1E has a warning device 38. The warning device 38 is, for example, a speaker or a display, Indicators, etc. The warning device 38 is based on the signal input from the control device 30E, Give a warning tone, Or display a warning message, Or, the light-emitting portion is turned on in a predetermined manner. As shown in FIG. 6B, The control device 30E includes the assisting force calculating unit 31E and the motor control unit 32, There may also be a theft determination unit 37, As its function. The stolen determination unit 37 when the vehicle is not traveling, Whether or not the vehicle is stolen is determined based on the posture change of the vehicle body (i.e., based on the acceleration detected by the acceleration sensor 54). E.g, The theft determination unit 37 determines that the vehicle is stolen when detecting an acceleration greater than the threshold. also, When the acceleration greater than the threshold continues for a longer period of time than the predetermined time, The theft determination unit 37 can also determine that the vehicle has been stolen. As still another example, When the vibration of the vehicle body detected by the acceleration sensor 54 meets a predetermined condition, The theft determination unit 37 can also determine that the vehicle has been stolen. In other words, The amplitude or direction of the vibration detected by the acceleration sensor 54, When the period is the case of the singer, The theft determination unit 37 can also determine that the vehicle has been stolen. E.g, When the vibration having an amplitude greater than the threshold continues for a long period of time at a predetermined time, The theft determination unit 37 can also determine that the vehicle has been stolen. As still another example, The electric assist bicycle 1E can also have: Locking mechanism, It is disposed on the rear wheel 6 or the front wheel 9; And switches, It detects the state of the locking mechanism (locked state/unlocked state). In this case, The theft determination unit 37 can also detect the state of the locking mechanism based on the output signal of the switch. and, For example, when the locking mechanism is in a locked state, And when the posture change or vibration of the above vehicle body is detected, The theft determination unit 37 can also determine that the vehicle has been stolen. When the control device 30E detects that the vehicle is stolen by the theft determination unit 37, The drive warning device 38 outputs a warning. in particular, The control device 30E emits a warning tone, Or display a warning, Or, the light-emitting portion is turned on in a predetermined manner. Furthermore, The warning device 38 is not necessarily a device mounted on the electric assist bicycle 1E. E.g, The warning device 38 can also be a mobile terminal owned by the user. In this case, The electric assist bicycle 1E includes a wireless communication device. Control device 30E can also be via a communication device, And send a warning to the mobile terminal owned by the user. In the fifth embodiment, The main switch (not shown) of the vehicle is turned off, Therefore, when the state of the power supply from the battery 22 to the electric motor 21 is not allowed, The control device 30E also executes the processing of the theft determination unit 37 by the power received from the battery built in the battery 22 or the control device 30E. The processing of the assisting force calculating unit 31E is the same as the processing performed by the assisting force calculating units 31A to 31D described so far. which is, The assisting force calculation unit 31E refers to the assist force, a mapping table or relationship between the pedaling force and the speed of the vehicle, Calculate the target assist force corresponding to the detected pedaling force and the vehicle speed. The control device 30E can also be the same as the control device 30A. There are 2 control modes. In the first control mode, The control device 30E determines that the vehicle is stolen based on the posture change of the vehicle body. A warning device that outputs a warning is detected when a situation in which the vehicle is stolen is detected. In the second control mode, The control device 30E does not perform the theft determination of the vehicle based on the posture change of the vehicle body. which is, In the second control mode, Control device 30E does not utilize the output of acceleration sensor 54 for the actuation of warning device 38. Control device 30E is also shown in Figure 6A. There is an operation unit 46. The control device 30E can selectively execute the first control mode and the second control mode based on the signal input from the operation unit 46. The choice of control mode by the user may not be possible. which is, The control device 30E can also constantly perform the control in the first control mode. In the form in which the control device 30E has two control modes, The theft determination unit 37 is executed only when the first control mode is selected via the operation unit 46. When selecting the second control mode, The theft determination unit 37 does not execute. FIG. 6C is a flowchart showing an example of processing executed by the theft determination unit 37. The theft determination unit 37 repeatedly executes the processing of one of the series shown in the figure at a specific cycle. In the form in which the control device 30E has two control modes, The processing of this flowchart is executed when the first control mode is selected. The theft determination unit 37 is based on, for example, an output signal of the front wheel rotation sensor 43. The vehicle speed is detected (S501). also, The theft determination unit 37 is based on the output signal of the acceleration sensor 54, The acceleration of the vehicle body (the posture change of the vehicle body) is detected (S502). and, The theft determination unit 37 determines whether the vehicle speed is lower than the threshold, That is, whether the vehicle is not traveling (S503). also, The theft determination unit 37 determines whether the posture change of the vehicle body obtained from the acceleration detected in S502 meets a predetermined condition. That is, whether the posture change is unique to the stolen (S504). in particular, For example, determining whether the posture change (acceleration) of the vehicle body is greater than a threshold value, Whether the amplitude of the vibration of the vehicle body or the like meets the predetermined conditions. At a speed below the threshold, And when the change in the posture of the vehicle body obtained from the acceleration meets a predetermined condition, The control device 30E determines that the vehicle is stolen. The warning device 38 is driven (S505). on the other hand, When the vehicle speed is above the threshold, Or when the posture change of the vehicle body obtained from the acceleration sensor 54 does not meet the predetermined condition, End this process. The present invention is not limited to the embodiments described above. Various changes are possible. E.g, The control device may also have a plurality of functions among the functions of the control devices 30A to 30E described above. E.g, The control device may have a function of smoothing the acceleration as described in the first embodiment. The function of detecting the dumping described in the fourth embodiment. In this case, A shared acceleration sensor can also be utilized in a plurality of functions.