US20150247536A1 - Clutch - Google Patents
Clutch Download PDFInfo
- Publication number
- US20150247536A1 US20150247536A1 US14/428,853 US201314428853A US2015247536A1 US 20150247536 A1 US20150247536 A1 US 20150247536A1 US 201314428853 A US201314428853 A US 201314428853A US 2015247536 A1 US2015247536 A1 US 2015247536A1
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- US
- United States
- Prior art keywords
- rotational body
- groove
- side rotational
- driven
- pin
- 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.)
- Abandoned
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Classifications
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- 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
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D41/00—Freewheels or freewheel clutches
- F16D41/06—Freewheels or freewheel clutches with intermediate wedging coupling members between an inner and an outer surface
- F16D41/08—Freewheels or freewheel clutches with intermediate wedging coupling members between an inner and an outer surface with provision for altering the freewheeling action
- F16D41/086—Freewheels or freewheel clutches with intermediate wedging coupling members between an inner and an outer surface with provision for altering the freewheeling action the intermediate members being of circular cross-section and wedging by rolling
- F16D41/088—Freewheels or freewheel clutches with intermediate wedging coupling members between an inner and an outer surface with provision for altering the freewheeling action the intermediate members being of circular cross-section and wedging by rolling the intermediate members being of only one size and wedging by a movement not having an axial component, between inner and outer races, one of which is cylindrical
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- 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
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D23/00—Details of mechanically-actuated clutches not specific for one distinct type
- F16D23/12—Mechanical clutch-actuating mechanisms arranged outside the clutch as such
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- 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
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D15/00—Clutches with wedging balls or rollers or with other wedgeable separate clutching members
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- 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
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D27/00—Magnetically- or electrically- actuated clutches; Control or electric circuits therefor
- F16D27/10—Magnetically- or electrically- actuated clutches; Control or electric circuits therefor with an electromagnet not rotating with a clutching member, i.e. without collecting rings
- F16D27/108—Magnetically- or electrically- actuated clutches; Control or electric circuits therefor with an electromagnet not rotating with a clutching member, i.e. without collecting rings with axially movable clutching members
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- 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
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D13/00—Friction clutches
- F16D13/76—Friction clutches specially adapted to incorporate with other transmission parts, i.e. at least one of the clutch parts also having another function, e.g. being the disc of a pulley
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- 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
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D23/00—Details of mechanically-actuated clutches not specific for one distinct type
- F16D23/12—Mechanical clutch-actuating mechanisms arranged outside the clutch as such
- F16D2023/123—Clutch actuation by cams, ramps or ball-screw mechanisms
Definitions
- the present disclosure relates to a clutch that switches the state of power transmission from a drive-side rotational body to a driven-side rotational body by switching the coupling state of the driven-side rotational body with respect to the drive-side rotational body.
- An engine that couples a mechanical pump, which circulates coolant, to the crankshaft through a clutch to operate the pump using rotational force of the crankshaft and disengages the clutch to stop operation of the pump.
- Clutches for switching the coupling state of the pump with respect to the crankshaft include a clutch having a drive-side rotational body coupled to the crankshaft and a driven-side rotational body, which is rotational relative to the drive-side rotational body. The clutch is maintained in the engaged state by pressing the rotational bodies against each other using magnetic force of magnets.
- Such clutches include a clutch described in Patent Document 1.
- the clutch described in Patent Document 1 includes a coil. To disengage the clutch, energization control is performed on the coil to generate a magnetic field that cancels the aforementioned magnetic force.
- Patent Document 1 Japanese Laid-Open Patent Publication No. 2010-203406
- the larger-sized coil enlarges the size of the clutch and increases power consumption. Therefore, the force needed for disengagement is therefore desired to be minimized while ensuring transmission of great torque.
- a clutch in accordance with one aspect of the present invention, includes a drive-side rotational body, a driven-side rotational body, an urging member, a groove, a pin, and a restricting portion.
- the driven-side rotational body is movable in an axial direction of the drive-side rotational body between a coupled position at which the driven-side rotational body is coupled to the drive-side rotational body and a decoupled position at which the driven-side rotational body is decoupled from the drive-side rotational body.
- the urging member urges the driven-side rotational body from the decoupled position toward the coupled position.
- the groove is formed in an outer circumferential surface of the driven-side rotational body.
- the groove has a helical portion that extends about an axis of the driven-side rotational body and an annular portion that is formed continuously from the helical portion and extends over an entire circumference of the driven-side rotational body and perpendicularly to the axial direction.
- the pin is selectively inserted into and retracted from the groove and restricted from moving in the axial direction.
- the position of the pin is shifted from the helical portion to the annular portion through rotation of the driven-side rotational body such that the driven-side rotational body is moved to the decoupled position against urging force of the urging member.
- the restricting portion restricts shifting of the position of the pin from the annular portion to the helical portion when the pin is in a state located in the annular portion.
- FIG. 1 is a cross-sectional view showing a clutch according to a first embodiment
- FIG. 2 is a side view showing the clutch shown in FIG. 1 in a disengaged state
- FIG. 3 is a side view showing the clutch of FIG. 1 in an engaged state
- FIG. 4 is a cross-sectional view illustrating the relationship between a groove of a driven-side rotational body and a stopper member and the configuration of an actuator for operating the stopper member;
- FIG. 5 is a side view showing a clutch according to a second embodiment in a disengaged state
- FIG. 6 is a side view showing the clutch illustrated in FIG. 5 in an engaged state
- FIG. 7 is a developed view showing a groove of the clutch of FIG. 5 ;
- FIG. 8 is a side view showing a clutch according to a third embodiment in a disengaged state
- FIG. 9 is a side view showing the clutch illustrated in FIG. 8 in an engaged state
- FIG. 10 is a developed view showing a groove of the clutch of FIG. 8 ;
- FIG. 11 is a developed view showing a groove of a modification of the third embodiment
- FIGS. 12A , 12 B, 12 C, and 12 D are schematic diagrams illustrating change of the state of a clutch according to a fourth embodiment
- FIGS. 13A , 13 B, 13 C, and 13 D are schematic diagrams illustrating change of the state of a clutch according to a fifth embodiment.
- FIG. 14 is a perspective view showing a driven-side rotational body according to another embodiment.
- a clutch according to a first embodiment will now be described with reference to FIGS. 1 to 4 .
- a clutch according to a first embodiment switches the state of power transmission from a crankshaft arranged in an engine to a water pump, which circulates coolant of the engine.
- a clutch 100 of the first embodiment is accommodated in an accommodating portion 310 , which is arranged in a housing 300 .
- a substantially cylindrical support member 320 is fitted in the housing 300 .
- An output shaft 210 of the clutch 100 is rotationally supported by the support member 320 through a first bearing 330 , which is located at an inner circumferential side of the support member 320 .
- An impeller 220 of a pump 200 is attached to a distal end portion (a right end portion as viewed in FIG. 1 ) of the output shaft 210 in a manner rotational integrally with the output shaft 210 .
- a drive-side rotational body 110 is rotationally supported by a proximal end portion (a left end portion as viewed in the drawing) of the output shaft 210 through a second bearing 340 .
- a straight spline 212 is formed in an outer circumferential surface of a portion of the output shaft 210 between the first bearing 330 and the second bearing 340 .
- a driven-side rotational body 120 is arranged between the housing 300 and the drive-side rotational body 110 .
- An engagement portion 121 which is meshed with the straight spline 212 of the output shaft 210 , is formed in an inner circumferential surface of the driven-side rotational body 120 .
- This configuration allows the driven-side rotational body 120 to rotate integrally with the output shaft 210 and move in the axial direction of the output shaft 210 .
- the output shaft 210 , the drive-side rotational body 110 , and the driven-side rotational body 120 are arranged coaxially with one another.
- the extending direction of the axis of these components will be referred to as the axial direction.
- the driven-side rotational body 120 has an outline including two columns that have different diameters and are joined coaxially with each other.
- the driven-side rotational body 120 is supported by the output shaft 210 in such an orientation that a large diameter portion 122 is located on the side close to the drive-side rotational body 110 (a left side as viewed in FIG. 1 ) and a small diameter portion 123 is arranged on the side close to the pump 200 (a right side as viewed in the drawing).
- a recess 124 having an opening facing the pump 200 is formed in the small diameter portion 123 of the driven-side rotational body 120 .
- a plurality of accommodating recesses 125 for accommodating urging members 135 are formed in a bottom portion of the recess 124 .
- the accommodating recesses 125 are arranged circumferentially in a manner surrounding the output shaft 210 .
- Each of the urging members 135 is, for example, a coil spring and accommodated in the corresponding one of the accommodating recesses 125 .
- Each urging member 135 has a distal end secured to a securing projection 211 , which projects from the output shaft 210 .
- the urging members 135 are accommodated in the corresponding accommodating recesses 125 each in a compressed state and urge the driven-side rotational body 120 toward the drive-side rotational body 110 (leftward as viewed in FIG. 1 ).
- a plurality of ball accommodating grooves 127 each for accommodating a corresponding one of balls 130 are formed in the large diameter portion 122 of the driven-side rotational body 120 and arranged circumferentially.
- An arcuate groove 111 which extends over the entire circumference of an inner circumferential surface of the drive-side rotational body 110 , is formed in the inner circumferential surface of the drive-side rotational body 110 .
- the arcuate groove 111 has an arcuate cross section.
- Each of the balls 130 is accommodated in the space formed by the corresponding one of the ball accommodating grooves 127 and the arcuate groove 111 .
- the driven-side rotational body 120 When the driven-side rotational body 120 is arranged at the position illustrated in FIG. 1 after having been moved toward the drive-side rotational body 110 by the urging force of the urging members 135 , the drive-side rotational body 110 and the driven-side rotational body 120 are coupled to each other through the balls 130 .
- the position at which the drive-side rotational body 110 and the driven-side rotational body 120 are coupled to each other, as illustrated in FIG. 1 will be referred to as a coupled position.
- a cup-like driven-side pulley 270 which surrounds the clutch 100 accommodated in the accommodating portion 310 of the housing 300 , is attached to the drive-side rotational body 110 .
- a drive-side pulley 260 is attached to an end portion of the crankshaft 250 in a manner rotational integrally with the crankshaft 250 .
- the drive-side pulley 260 and the driven-side pulley 270 are coupled to each other through a belt 280 , which is looped over the drive-side pulley 260 and the driven-side pulley 270 .
- the drive-side rotational body 110 rotates in a clockwise direction as viewed from the side corresponding to the distal end of the output shaft 210 (the side corresponding to the right end as viewed in FIGS. 2 and 3 ) toward the drive-side rotational body 110 .
- each of the ball accommodating grooves 127 which are formed in the large diameter portion 122 of the driven-side rotational body 120 , extends in the axial direction from an end surface of the large diameter portion 122 before being curved and then extends in the rotational direction of the drive-side rotational body 110 .
- a finishing end of each ball accommodating groove 127 forms a holding portion 128 .
- each ball accommodating groove 127 becomes smaller in the rotational direction of the drive-side rotational body 110 such that the depth of the holding portion 128 is minimized.
- the balls 130 are non-rotational when the driven-side rotational body 120 is arranged at the coupled position illustrated in FIG. 3 .
- This allows the driven-side rotational body 120 to rotate together with the drive-side rotational body 110 . That is, when the driven-side rotational body 120 is located at the coupled position, the balls 130 are caught between the driven-side rotational body 120 and the drive-side rotational body 110 in a non-rotational manner, thus coupling the driven-side rotational body 120 to the drive-side rotational body 110 .
- the driven-side rotational body 120 when the driven-side rotational body 120 is arranged at the position illustrated in FIG. 2 , the balls 130 are released from the holding portions 128 and received in the axially extended portions of the corresponding ball accommodating grooves 127 . Specifically, a substantially half of each ball 130 is accommodated in the arcuate groove 111 of the drive-side rotational body 110 . This restricts axial movement of the ball 130 relative to the drive-side rotational body 110 .
- each ball 130 is received in the axially extended portion, which has a depth greater than the depth of each holding portion 128 , after having been released from the holding portion 128 with a smaller depth, the ball 130 is released from the driven-side rotational body 120 and the drive-side rotational body 110 .
- the drive-side rotational body 110 and the driven-side rotational body 120 are allowed to rotate relative to each other. That is, the driven-side rotational body 120 is decoupled from the drive-side rotational body 110 .
- decoupled position out of the axial positions of the driven-side rotational body 120 moving axially along the output shaft 210 , the position at which the drive-side rotational body 110 and the driven-side rotational body 120 are decoupled from each other as illustrated in FIG. 2 will be referred to as a decoupled position.
- a circumferential groove 400 is formed in an outer circumferential surface of the small diameter portion 123 of the driven-side rotational body 120 .
- the groove 400 includes a helical groove 410 serving as a helical portion extending about the axis in a manner inclined with respect to the axial direction and an annular groove 420 serving as an annular portion extending perpendicular to the axial direction.
- the helical groove 410 extends in a manner revolving on the outer circumferential surface of the driven-side rotational body 120 by one cycle and inclined such that the helical groove 410 approaches the drive-side rotational body 110 toward the trailing end in the rotational direction of the drive-side rotational body 110 .
- the annular groove 420 is formed continuously from the helical groove 410 and extends over the entire circumference of the outer circumferential surface of the driven-side rotational body 120 . The configuration of the groove 400 will be described in detail below.
- the clutch 100 includes a locking member 140 and an actuator 150 for selectively inserting and retracting a pin 141 , which is arranged at the distal end of the locking member 140 , with respect to the groove 400 .
- the axial position of the locking member 140 is restricted. As illustrated in FIG. 3 , the axial position of the locking member 140 is set such that the pin 141 is inserted into a portion of the helical groove 410 of the groove 400 in the vicinity of a starting end 411 when the driven-side rotational body 120 is arranged at the coupled position.
- the pin 141 is inserted into the portion of the helical groove 410 in the vicinity of the starting end 411 . After having been inserted into the helical groove 410 , the pin 141 is engaged with a side wall 413 of the helical groove 410 , thus locking the driven-side rotational body 120 against the urging force of the urging members 135 .
- the driven-side rotational body 120 is rotated with the pin 141 engaged with the side wall 413 of the helical groove 410 . Then, while the pin 141 slides on the side wall 413 of the helical groove 410 , the driven-side rotational body 120 moves axially from the coupled position toward the decoupled position. When the pin 141 reaches a finishing end 412 of the helical groove 410 , the pin 141 is inserted into the annular groove 420 and the driven-side rotational body 120 is switched from the coupled position to the decoupled position.
- the clutch 100 is configured such that, by inserting the pin 141 of the looking member 140 into the groove 400 to engage the pin 141 with the side wall 413 of the helical groove 410 , the driven-side rotational body 120 is moved to the decoupled position against the urging force of the urging members 135 .
- the driven-side rotational body 120 is urged toward the coupled position by the urging force of the urging members 135 . Accordingly, to maintain the decoupled state, the pin 141 of the locking member 140 must be maintained in a state inserted in the annular groove 420 of the driven-side rotational body 120 .
- the pin 141 is retracted from the annular groove 420 of the groove 400 by means of the actuator 150 . After the pin 141 is retracted in this manner, the locking member 140 is disengaged from the driven-side rotational body 120 and the driven-side rotational body 120 is moved to the coupled position by the urging force of the urging members 135 . As a result, the drive-side rotational body 110 and the driven-side rotational body 120 are returned to the coupled state.
- the annular groove 420 is formed continuously from the helical groove 410 and extends over the entire circumference of the outer circumferential surface of the driven-side rotational body 120 .
- the groove 400 of the driven-side rotational body 120 thus has a connecting portion at which the annular groove 420 and the helical groove 410 are connected to each other.
- the clutch 100 of the first embodiment includes a restricting portion, which restricts such shifting of the pin 141 from the annular groove 420 to the helical groove 410 when the pin 141 is inserted in the annular groove 420 .
- the restricting portion is configured in the manner described below. That is, in the groove 400 , as illustrated in FIGS. 2 to 4 , the annular groove 420 has a depth greater than the depth of the helical groove 410 . In other words, the bottom surface of the annular groove 420 is located radially inward of the bottom surface of the helical groove 410 .
- the annular groove 420 and the helical groove 410 are thus connected together with a step formed between the annular groove 420 and the helical groove 410 .
- the step which is the side wall 423 of the annular groove 420 , functions as the restricting portion.
- the width of the helical groove 410 becomes gradually smaller from the starting end 411 to the finishing end 412 . Therefore, when the inserting position of the pin 141 , which has been inserted into the portion of the helical groove 410 in the vicinity of the starting end 411 , reaches the finishing end 412 of the helical groove 410 as the driven-side rotational body 120 rotates, the pin 141 is pressed by the side wall 413 of the helical groove 410 and thus inserted into the annular groove 420 , which has a depth greater than the depth of the helical groove 410 .
- the depth of the helical groove 410 becomes gradually greater from the starting end 411 to the finishing end 412 .
- the radial position of the bottom surface of the helical groove 410 approaches the axis of the driven-side rotational body 120 gradually from the starting end 411 to the finishing end 412 .
- the depth of the annular groove 420 is small at the starting end 421 of the annular groove 420 , which corresponds to the finishing end 412 of the helical groove 410 , relative to the depths of the other portions in the circumferential direction of the driven-side rotational body 120 .
- the radial distance between the bottom surface of the annular groove 420 and the bottom surface of the helical groove 410 is thus small at the portion corresponding to the finishing end 412 of the helical groove 410 and the starting end 421 of the annular groove 420 , relative to other portions. That is, at this portion, the step between the helical groove 410 and the annular groove 420 is relatively small. This attenuates impact applied to the pin 141 when the pin 141 reaches the finishing end 412 of the helical groove 410 and is then inserted into the annular groove 420 , which has a depth greater than the depth of the helical groove 410 , compared to a case in which the size of the step is set uniform in the circumferential direction. Specifically, the step at the aforementioned portion is set to such a size that the aforementioned impact is attenuated and shifting of the pin 141 from the annular groove 420 to the helical groove 410 is restrained.
- the actuator 150 of the first embodiment is an electromagnetic actuator, which is operated through action of a magnetic field generated by energizing a coil 153 accommodated in a first case 152 .
- the first case 152 has a cylindrical shape having a bottom portion and a fixed core 154 is fixed to the bottom portion.
- the coil 153 is arranged in the first case 152 to surround the fixed core 154 . That is, in the actuator 150 , the fixed core 154 and the coil 153 configure an electromagnet.
- a movable core 155 is movably accommodated in the coil 153 of the first case 152 at a position facing the fixed core 154 .
- the fixed core 154 and the movable core 155 of the first embodiment are both iron cores.
- a cylindrical second case 158 is fixed to a distal end portion (a right end portion as viewed in FIG. 4 ) of the first case 152 .
- a permanent magnet 159 is fixed to an end portion of the second case 158 fixed to the first case 152 in a manner surrounding the movable core 155 .
- the movable core 155 is accommodated in the first case 152 such that a proximal end zone (a left end zone as viewed in FIG. 4 ) of the movable core 155 faces the fixed core 154 .
- a distal end zone projects outward from the second case 158 .
- a ring member 160 is attached to the portion of the movable core 155 that is accommodated in the second case 158 .
- a coil spring 161 which has an end secured to the second case 158 and an opposite end secured to the ring member 160 , is accommodated in the second case 158 in a compressed state.
- the coil spring 161 urges the movable core 155 in the direction in which the movable core 155 projects from the second case 158 (rightward as viewed in FIG. 4 ).
- the portion of the movable core 155 that projects from the second case 158 is coupled to the locking member 140 through a fixing pin 162 .
- the locking member 140 is pivotally coupled to the movable core 155 at the proximal end of the locking member 140 and pivotally supported by a pivot shaft 156 .
- This allows the locking member 140 to pivot about the pivot shaft 156 , which is a support point of pivot, when the movable core 155 moves.
- the pin 141 of the locking member 140 is inserted sequentially into the helical groove 410 and the annular groove 420 of the driven-side rotational body 120 .
- the locking member 140 is pivoted clockwise as viewed in FIG. 4 to retract the distal end of the locking member 140 from the groove 400 . That is, the actuator 150 retracts the locking member 140 from the groove 400 by attracting the movable core 155 using magnetic force produced through energization of the coil 153 .
- the movable core 155 After the movable core 155 is attracted and moved to a contact position at which the movable core 155 contacts the fixed core 154 (the position represented by the long dashed double-short dashed lines in FIG. 4 ), the movable core 155 is held in contact with the fixed core 154 by the magnetic force of the permanent magnet 159 even if the energization is stopped afterwards.
- the coil 153 is energized by an electric current flowing in the opposite direction to the direction of the electric current for attracting the movable core 155 when the movable core 155 is arranged at the contact position represented by the long dashed double-short dashed lines in FIG. 4 , a magnetic field is generated in the opposite direction to the direction of the magnetic field of the permanent magnet 159 .
- This attenuates the attracting force of the permanent magnet 159 , and the movable core 155 is separated from the fixed core 154 by the urging force of the coil spring 161 .
- the movable core 155 then moves to the projected position represented by the solid lines in FIG. 4 .
- the locking member 140 is pivoted counterclockwise as viewed in FIG. 4 and the pin 141 of the locking member 140 is inserted into the groove 400 .
- the urging force of the coil spring 161 exceeds the attracting force of the permanent magnet 159 .
- the coil 153 is energized to separate the movable core 155 from the fixed core 154 , the movable core 155 is held at the projected position even after such energization is stopped afterward.
- the actuator 150 of the first embodiment is a self-holding type solenoid, which switches the engagement state of the clutch 100 by applying direct electric currents in different directions and thus moving the movable core 155 and does not need the energization to maintain the clutch 100 in either the engaged state or the disengaged state.
- the movable core 155 is moved from the contact position to the projected position represented by the solid lines in FIG. 4 by the urging force of the coil spring 161 .
- This pivots the locking member 140 counterclockwise as viewed in FIG. 4 thus inserting the pin 141 of the locking member 140 into the portion of the helical groove 410 of the groove 400 of the driven-side rotational body in the vicinity of the starting end 411 .
- the driven-side rotational body 120 is thus stopped and held in the state illustrated in FIG. 3 .
- the driven-side rotational body 120 When the driven-side rotational body 120 is rotated together with the drive-side rotational body 110 with the pin 141 locking the driven-side rotational body 120 and the pin 141 is moved relatively in the helical groove 410 , the driven-side rotational body 120 is moved from the coupled position to the decoupled position and thus switched from the state illustrated in FIG. 3 to the state illustrated in FIG. 2 . In this manner, the pin 141 is switched to a state inserted in the annular groove 420 and the driven-side rotational body 120 reaches the decoupled position. This stops transmission of rotation of the drive-side rotational body 110 to the driven-side rotational body 120 , thus disengaging the clutch 100 .
- the driven-side rotational body 120 is continuously rotated by inertial force while receiving action of friction force produced between the driven-side rotational body 120 and the pin 141 , which is inserted in the annular groove 420 as shown in FIG. 2 .
- the pin 141 is engaged with the step in the boundary between the helical groove 410 and the annular groove 420 , which is the side wall 423 of the annular groove 420 .
- the pin 141 unless the pin 141 is shifted to be retracted from the annular groove 420 and thus move past the step, the pin 141 cannot be shifted into the helical groove 410 , so that shifting of the pin 141 from the annular groove 420 into the helical groove 410 is restricted.
- the driven-side rotational body 120 is rotated with the pin 141 of the locking member 140 inserted in the annular groove 420 of the driven-side rotational body 120 .
- the rotational speed of the driven-side rotational body 120 then decreases gradually until the driven-side rotational body 120 eventually stops rotating.
- the coil 153 of the actuator 150 is energized to generate a magnetic field in the same direction as the direction of the magnetic field of the permanent magnet 159 .
- the movable core 155 is thus attracted toward the fixed core 154 by magnetic force produced by energization and moved from the projected position represented by the solid lines in FIG. 4 to the contact position represented by the long dashed double-short dashed lines in the drawing. This pivots the locking member 140 clockwise as viewed in FIG. 4 , thus fully retracting the pin 141 of the locking member 140 from the groove 400 .
- the driven-side rotational body 120 After having been released from the locking member 140 , the driven-side rotational body 120 is moved to the coupled position by the urging force of the urging members 135 .
- the driven-side rotational body 120 and the drive-side rotational body 110 thus become coupled to each other, switching the clutch 100 to the engaged state.
- the depth of the annular groove 420 is small in the vicinity of the starting end 421 relative to the depths of the other portions in the circumferential direction of the driven-side rotational body 120 .
- the depth of the helical groove 410 becomes gradually greater from the starting end 411 to the finishing end 412 .
- the step between the finishing end 412 of the helical groove 410 and the starting end 421 of the annular groove 420 is small-sized relative to steps in other portions.
- a clutch according to a second embodiment will now be described with reference to FIGS. 5 to 7 .
- a clutch 500 of the second embodiment is different from the first embodiment in terms of the configuration of a groove 520 formed in an outer circumferential surface of a small diameter portion 511 of a driven-side rotational body 510 and the configuration of a pin 560 of a locking member 550 .
- the remainder of the configuration is the same as those of the first embodiment.
- like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted.
- the groove 520 of the driven-side rotational body 510 has a helical groove 530 inclined with respect to the axial direction and an annular groove 540 , which is formed continuously from the helical groove 530 and extends over the entire circumference of an outer circumferential surface of the driven-side rotational body 510 and perpendicularly to the axial direction.
- the annular groove 540 has a connecting portion 541 , which has a depth equal to the depth of the helical groove 530 and is connected to the helical groove 530 , and a non-connecting portion 542 , which is disconnected from the helical groove 530 .
- the boundary between the connecting portion 541 of the annular groove 540 and the helical groove 530 is represented by the long dashed double-short dashed line.
- the long dashed double-short dashed line representing the boundary coincides with the extended line of a side wall 544 of the non-connecting portion 542 of the annular groove 540 .
- a protrusion 543 which protrudes from the bottom surface of the annular groove 540 and extends in the extending direction of the annular groove 540 , is formed in the annular groove 540 .
- the protrusion 543 is formed over the entire length of the connecting portion 541 .
- the opposite ends of the protrusion 543 are arranged in the non-connecting portion 542 .
- the protrusion 543 of the annular groove 540 has a uniform width and is inclined with respect to the axial direction of the driven-side rotational body 510 by the inclination angle equal to the inclination angle of a side wall 531 of the helical groove 530 .
- the distance from the side wall 531 of the helical groove 530 to the protrusion 543 is a uniform distance d 1 in the circumferential direction of the driven-side rotational body 510 .
- a recess 561 into which the protrusion 543 can proceed, is formed at the distal end of the pin 560 of the locking member 550 .
- states of relative movement of the pin 560 of the locking member 550 in the groove 520 when the driven-side rotational body 510 is in a rotating state are illustrated by way of pins 560 represented by the long dashed double-short dashed lines.
- the protrusion 543 which projects from the bottom surface of the annular groove 540 , and the recess 561 of the pin 560 configure a restricting portion.
- the width d 2 of the pin 560 of the locking member 550 is slightly smaller than the distance d 1 from the side wall 531 of the helical groove 530 to the protrusion 543 .
- the distance d 3 from a starting end of the protrusion 543 which is the end portion of the protrusion 543 that the pin 560 reaches first when the driven-side rotational body 510 is rotated, to the side wall 544 of the annular groove 540 is substantially equal to but slightly greater than the length d 4 from the side surface of the pin 560 to the recess 561 .
- the width d 5 of the recess 561 is greater than the width d 6 of the protrusion 543 .
- the actuator 150 is operated to insert the pin 560 of the locking member 550 into a starting end 532 of the helical groove 530 of the groove 520 .
- the pin 560 is moved relatively in the groove 520 in a circumferential direction while being engaged with the side wall 531 of the helical groove 530 .
- the width d 2 of the pin 560 is slightly smaller than the distance d 1 from the side wall 531 of the helical groove 530 to the protrusion 543 . This restrains interference of the protrusion 543 with movement of the pin 560 when the pin 560 is engaged with the side wall 531 of the helical groove 530 and moved relatively in the groove 520 , thus allowing relative movement of the pin 560 in the helical groove 530 .
- the pin 560 thus reaches the annular groove 540 and is then moved relatively in the annular groove 540 of the groove 520 as the driven-side rotational body 510 is rotated.
- the driven-side rotational body 510 is rotated by inertial force at the decoupled position.
- the distance d 3 from the starting end of the protrusion 543 to the side wall 544 of the annular groove 540 is substantially equal to but slightly greater than the length d 4 from the side wall of the pin 560 to the recess 561 .
- the width d 5 of the recess 561 is greater than the width d 6 of the protrusion 543 . Therefore, when the driven-side rotational body 510 is rotated and the pin 560 is moved relatively in the annular groove 540 to reach the starting end of the protrusion 543 , which is arranged in the annular groove 540 , the protrusion 543 proceeds into the recess 561 and becomes engaged with the recess 561 .
- the protrusion 543 extends in the extending direction of the annular groove 540 and is formed over the entire length of the connecting portion 541 .
- the actuator 150 is operated to retract the pin 560 of the locking member 550 from the annular groove 540 of the groove 520 . This also causes disengagement between the recess 561 of the pin 560 and the protrusion 543 of the annular groove 540 .
- the driven-side rotational body 510 is moved to the coupled position by the urging force of the urging members 135 .
- the driven-side rotational body 510 and the drive-side rotational body 110 thus become coupled to each other, switching the clutch 500 to the engaged state.
- the second embodiment achieves the following advantage (4) as well as an advantage equivalent to the advantage (1) of the first embodiment.
- shifting of the pin 560 from the annular groove 540 to the helical groove 530 is restricted unless the pin 560 is shifted to be retracted from the annular groove 540 and the recess 561 of the pin 560 and the protrusion 543 of the annular groove 540 are disengaged from each other. That is, when the pin 560 is inserted in the annular groove 540 , the recess 561 of the pin 560 and the protrusion 543 of the annular groove 540 function as a restricting portion.
- a clutch according to a third embodiment will now be described with reference to FIGS. 8 to 10 .
- a clutch 600 of the third embodiment is different from the illustrated embodiments in terms of the configuration of a groove 620 formed in an outer circumferential surface of a small diameter portion 611 of a driven-side rotational body 610 and the configuration of a pin 660 of a locking member 650 .
- the remainder of the configuration is the same as those of the first embodiment.
- like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted.
- the groove 620 of the driven-side rotational body 610 has a helical groove 630 inclined with respect to the axial direction and an annular groove 640 , which is formed continuously from the helical groove 630 and extends over the entire circumference of an outer circumferential surface of the driven-side rotational body 610 and perpendicularly to the axial direction.
- the annular groove 640 has a connecting portion 641 , which has a depth equal to the depth of the helical groove 630 and is connected directly to the helical groove 630 , and a non-connecting portion 642 , which is not connected directly to the helical groove 630 .
- the boundary between the connecting portion 641 of the annular groove 640 and the helical groove 630 is represented by the long dashed double-short dashed line.
- the long dashed double-short dashed line representing the boundary coincides with the extended line of a side wall 644 of the non-connecting portion 642 of the annular groove 640 .
- a recessed groove 643 which extends in the extending direction of the annular groove 640 , is formed in the annular groove 640 .
- the recessed groove 643 extends in a direction perpendicular to the axial direction of the driven-side rotational body 610 .
- the recessed groove 643 extends over the entire length of the annular groove 640 . That is, the recessed groove 643 is formed over the entire circumference of the outer circumferential surface of the driven-side rotational body 610 .
- a projection 661 which can be inserted into the recessed groove 643 , projects from the distal end of the pin 660 of the locking member 650 .
- states of relative movement of the pin 660 of the locking member 650 in the groove 620 when the driven-side rotational body 610 is in a rotating state are illustrated by pins 660 represented by the long dashed double-short dashed lines.
- the recessed groove 643 which is formed in the bottom surface of the annular groove 640 , and the projection 661 of the pin 660 configure a restricting portion.
- the length d 1 from the side surface of the pin 660 of the locking member 650 to the projection 661 is substantially equal to but slightly greater than the distance d 2 from the side wall 644 of the annular groove 640 to the recessed groove 643 .
- the width d 3 of the projection 661 of the pin 660 is smaller than the width d 4 of the recessed groove 643 of the annular groove 640 .
- the actuator 150 is operated to insert the pin 660 of the locking member 650 into a starting end 632 of the helical groove 630 of the groove 620 .
- the pin 660 is moved relatively in the groove 620 in a circumferential direction while being engaged with the side wall 631 of the helical groove 630 .
- the pin 660 thus reaches the annular groove 640 and the driven-side rotational body 610 is moved to a decoupled position and rotated by inertial force. As a result, with reference to FIG. 8 , the pin 660 is switched to a state moving relatively in the annular groove 640 .
- the length d 1 from the side surface of the pin 660 of the locking member 650 to the projection 661 is substantially equal to but slightly greater than the distance d 2 from the side wall 644 of the annular groove 640 to the recessed groove 643 .
- the width d 3 of the projection 661 of the pin 660 is smaller than the width d 4 of the recessed groove 643 of the annular groove 640 . Therefore, when the driven-side rotational body 610 is rotated and the pin 660 is moved relatively in the annular groove 640 , the projection 661 of the pin 660 proceeds into the recessed groove 643 , which is formed in the annular groove 640 , and becomes engaged with the recessed groove 643 .
- the recessed groove 643 extends in the extending direction of the annular groove 640 and is formed over the entire length of the annular groove 640 .
- the actuator 150 is operated to retract the pin 660 of the locking member 650 from the annular groove 640 of the groove 620 .
- This also causes retraction of the projection 661 of the pin 660 from the recessed groove 643 of the annular groove 640 , thus disengaging the projection 661 of the pin 660 and the recessed groove 643 of the annular groove 640 from each other.
- the driven-side rotational body 510 is then moved to the coupled position by the urging force of the urging members 135 .
- the driven-side rotational body 510 and the drive-side rotational body 110 become coupled to each other, thus switching the clutch 500 to the engaged state.
- the third embodiment achieves the following advantage (5) as well as an advantage equivalent to the advantage (1) of the first embodiment.
- shifting of the pin 660 from the annular groove 640 to the helical groove 630 is restricted unless the pin 660 is shifted to be retracted from the annular groove 640 and the recessed groove 643 and the projection 661 of the pin 660 are disengaged from each other. That is, when the pin 660 is inserted in the annular groove 640 , the recessed groove 643 and the projection 661 of the pin 660 function as a restricting portion. As a result, since shifting of the pin 660 from the annular groove 640 to the helical groove 630 is restricted, it is possible to restrain shifting of the driven-side rotational body 610 to the coupled position despite the fact that the pin 660 is maintained in the recessed groove 643 .
- the present modification is different from the third embodiment in terms of the configuration of a helical groove 680 of a groove 670 of the driven-side rotational body.
- a recessed groove 681 which extends in the extending direction of the helical groove 680 , is formed also in the helical groove 680 .
- the recessed groove 681 of the helical groove 680 is connected to the recessed groove 643 of the annular groove 640 .
- the actuator 150 is operated to insert the pin 660 of the locking member 650 into the helical groove 630 of the groove 620 when the driven-side rotational body 610 is in a state coupled to the drive-side rotational body 110 , the pin 660 becomes engaged with the side wall 631 of the helical groove 630 . Also, the projection 661 of the pin 660 proceeds into the recessed groove 681 of the helical groove 680 and becomes engaged with the recessed groove 681 . Then, when the driven-side rotational body is rotated and the pin 660 is moved relatively in the helical groove 630 , engagement between the projection 661 and the recessed groove 681 is maintained. In this state, where such engagement is maintained, the pin 660 reaches the annular groove 640 .
- the projection 661 proceeds into the recessed groove 643 of the annular groove 640 through the connecting portion between the recessed groove 681 of the helical groove 680 and the recessed groove 643 of the annular groove 640 . That is, the recessed groove 681 of the helical groove 680 guides the projection 661 of the pin 660 into the recessed groove 643 of the annular groove 640 .
- the recessed groove 643 extends in the extending direction of the annular groove 640 and is formed over the entire length of the annular groove 640 .
- a clutch according to a fourth embodiment will now be described with reference to FIG. 12 .
- a clutch 700 of the fourth embodiment is different from the illustrated embodiments in terms of the configuration of a driven-side rotational body 710 and the configuration of a locking member 750 .
- the remainder of the configuration is the same as those of the first embodiment.
- like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted.
- Position change of each ball 130 in the corresponding ball accommodating groove 127 caused by axial shifting of the driven-side rotational body 710 and switching between the engaged state and the disengaged state caused by such position change happen in the same manners as the first embodiment. Accordingly, illustration of the balls 130 and the ball accommodating grooves 127 are omitted in FIG. 12 .
- a groove 720 of a small diameter portion 711 of the driven-side rotational body 710 includes a helical groove 730 inclined with respect to the axial direction and an annular groove 740 , which is formed continuously from the helical groove 730 and extends over the entire circumference of an outer circumferential surface of the driven-side rotational body 710 and perpendicularly to the axial direction.
- the annular groove 740 of the groove 720 has a depth equal to the depth of the helical groove 730 .
- the boundary between a connecting portion of the annular groove 740 which is connected directly to the helical groove 730 , and the helical groove 730 is represented by the long dashed double-short dashed line.
- a flange 770 projects from the outer circumferential surface of the driven-side rotational body 710 and extends over the entire circumference of the outer circumferential surface of the driven-side rotational body 710 .
- the flange 770 is arranged on an outer circumferential surface of the small diameter portion 711 of the driven-side rotational body 710 . That is, the flange 770 is formed at a right side as viewed in FIG. 12A with respect to a groove 720 in the outer circumferential surface of the driven-side rotational body.
- the flange 770 extends perpendicular to the axial direction of the driven-side rotational body 710 and parallel to the annular groove 740 .
- the locking member 750 includes a pin 760 , which is inserted into the groove 720 of the driven-side rotational body 710 , and a one-way locking portion 780 , which selectively proceeds and retreats with respect to the driven-side rotational body 710 as the pin 760 is inserted into or retracted from the groove 720 .
- the one-way locking portion 780 and the flange 770 of the driven-side rotational body 710 configure a restricting portion.
- the one-way locking portion 780 includes an engagement member 781 and an elastic member 785 , which urges the engagement member 781 toward the driven-side rotational body 710 .
- the elastic member 785 is configured by, for example, a coil spring.
- the one-way locking portion 780 is located at the same side with respect to the pin 760 as the side at which the flange 770 is arranged with respect to the groove 720 (the right side as viewed in FIG. 12A ).
- the right surface of the flange 770 as viewed in FIG. 12A is referred to as a first surface 771 and the left surface of the flange 770 as viewed in the drawing is referred to as a second surface 772 .
- the right surface of the engagement member 781 as viewed in FIG. 12A is referred to as a first surface 782 and the left surface of the engagement member 781 as viewed in the drawing is referred to as a second surface 783 .
- the right surface of the pin 760 as viewed in FIG. 12A is referred to as a first surface 761 .
- the distances between the respective surfaces and the shapes of the surfaces 782 , 783 of the engagement member 781 are defined as follows.
- the distance d 1 from the first surface 761 of the pin 760 to the second surface 783 of the engagement member 781 is substantially equal to but slightly greater than the distance d 2 from a side wall 732 at a starting end 731 of the helical groove 730 to the first surface 771 of the flange 770 .
- the distance d 3 from the first surface 761 of the pin 760 of the locking member 750 to the first surface 782 of the engagement member 781 is substantially equal to but slightly smaller than the distance d 4 from a side wall 741 of the annular groove 740 (the position represented by the long dashed double-short dashed line in the connecting portion of the annular groove 740 ) to the second surface 772 of the flange 770 .
- the distal end of the first surface 782 is a corner and the distal end of the second surface 783 is a chamfered round surface. That is, the second surface 783 is inclined such that the first surface 782 approaches the first surface 782 in a distal direction. In other words, the distal end of the engagement member 781 is inclined and becomes gradually smaller in size.
- the second surface 783 of the engagement member 781 is in contact with the first surface 771 of the flange 770 .
- the second surface 783 of the engagement member 781 which contacts the flange 770 at this stage, has the inclined distal end as has been described.
- FIG. 12D when the pin 760 is inserted in the annular groove 740 of the groove 720 , the engagement member 781 is in contact with the second surface 772 of the flange 770 .
- the distal end of the first surface 782 of the engagement member 781 which contacts the flange 770 at this stage, is the corner as has been described.
- the driven-side rotational body 710 is located at a coupled position and the driven-side rotational body 710 is in a state coupled to the drive-side rotational body 110 .
- the state illustrated in. FIG. 12B is brought about.
- the pin 760 is engaged with a side wall 732 of the helical groove 730 , thus locking the driven-side rotational body 120 against the urging force of the urging members 135 .
- the pin 760 is moved relatively in the groove 720 in a circumferential direction while being engaged with the side wall 732 of the helical groove 730 .
- the driven-side rotational body 710 is thus shifted from the coupled position to a decoupled position.
- the position of the pin 760 in the groove 720 is shifted relatively in a direction from the helical groove 730 toward the annular groove 740 .
- the engagement member 781 which is fixed to the locking member 750 together with the pin 760 , is shifted relative to the driven-side rotational body 710 .
- the engagement member 781 faces the first surface 771 of the flange 770 .
- the second surface 783 of the engagement member 781 which faces the flange 770 , has the inclined distal end.
- the surface by which the engagement member 781 contacts the flange 770 when the driven-side rotational body 710 is shifted from the coupled position to the decoupled position is inclined. Therefore, when the driven-side rotational body 710 is moved from the coupled position to the decoupled position, the flange 770 and the engagement member 781 contact each other, as illustrated in FIG. 12C , to cause the force for pressing the engagement member 781 back against the urging force of the elastic member 785 such that the engagement member 781 moves past the flange 770 .
- the actuator 150 is operated to retract the pin 760 of the locking member 750 from the annular groove 740 of the groove 720 . This also causes disengagement between the engagement member 781 and the flange 770 .
- the driven-side rotational body 710 is thus moved to the coupled position by the urging force of the urging members 135 . As a result, the driven-side rotational body 710 and the drive-side rotational body 110 become coupled to each other, thus switching the clutch 700 to the engaged state.
- the fourth embodiment achieves the following advantage (6) as well as an advantage equivalent to the advantage (1) of the first embodiment.
- the pin 760 is not shifted from the annular groove 740 to the helical groove 730 . That is, the flange 770 and the one-way locking portion 780 function as a restricting portion. This restricts shifting of the pin 760 from the annular groove 740 to the helical groove 730 when the pin 760 is inserted in the annular groove 740 . As a result, it is possible to restrain shifting of the driven-side rotational body 710 to the coupled position despite the fact that the pin 760 is maintained in the groove 720 .
- a clutch 800 of the fifth embodiment is different from the fourth embodiment in terms of the configuration of the locking member 750 .
- the remainder of the configuration is the same as those of the first embodiment.
- like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted.
- the fifth embodiment is the same as the first embodiment in terms of position change of each ball 130 in the corresponding ball accommodating groove 127 caused by axial shifting of the driven-side rotational body 710 and switching between the engaged state and the disengaged state caused by such position change. Accordingly, illustration of the balls 130 and the ball accommodating grooves 127 is omitted also in FIG. 13 .
- the driven-side rotational body 710 of the fifth embodiment is configured identically with the driven-side rotational body 710 of the fourth embodiment.
- the flange 770 is formed in the driven-side rotational body 710 .
- a locking member 850 includes a pin 860 , which is inserted into the groove 720 of the driven-side rotational body 710 , and a one-way locking portion 880 , which selectively proceeds and retreats with respect to the driven-side rotational body 710 as the pin 860 is inserted into or retracted from the groove 720 .
- the one-way locking portion 880 and the flange 770 of the driven-side rotational body 710 configure a restricting portion.
- the one-way locking portion 880 includes an engagement member 881 , a pivot shaft 885 through which the engagement member 881 is pivotally supported by the locking member 850 , and a restricting member 888 , which restricts pivot of the engagement member 881 in a certain direction (a leftward direction in FIG. 13A ).
- a state in which the distal end of the engagement member 881 projects toward the driven-side rotational body 710 is defined as a reference position of the engagement member 881 .
- the restricting member 888 restricts tilting of the engagement member 881 in a specific direction from the reference position and permits tilting of the engagement member 881 in another direction (a rightward direction in FIG. 13A ) from the reference position.
- the right surface of the flange 770 as viewed in FIG. 13A is referred to as the first surface 771 and the left surface of the flange 770 as viewed in the drawing is referred to as the second surface 772 .
- the right surface of the engagement member 881 as viewed in FIG. 13A and the left surface of the engagement member 881 as viewed in the drawing when the engagement member 881 is arranged at the reference position are referred to as a first surface 882 and a second surface 883 , respectively.
- the right surface of the pin 860 as viewed in FIG. 13A is referred to as a first surface 861 .
- the distances between the respective surfaces are defined as follows.
- the distance d 1 from the first surface 861 of the pin 860 to the second surface 883 of the engagement member 881 is substantially equal to but slightly greater than the distance d 2 from the side wall 732 of the helical groove 730 at the starting end 731 to the first surface 771 of the flange 770 .
- the distance d 3 from the first surface 861 of the pin 860 of the locking member 850 to the first surface 882 of the engagement member 881 is substantially equal to but slightly smaller than the length d 4 from the side wall 741 of the annular groove 740 (the position represented by the long dashed double-short dashed line corresponding to the boundary position between the annular groove 740 and the helical groove 730 in the connecting portion of the annular groove 740 ) to the second surface 772 of the flange 770 .
- the driven-side rotational body 710 is in a coupled state and the pin 860 is inserted in the starting end 731 of the helical groove 730 of the groove 720 as illustrated in FIG. 13B , the second surface 883 of the engagement member 881 is in contact with the first surface 771 of the flange 770 .
- the engagement member 881 is in contact with the second surface 772 of the flange 770 .
- the driven-side rotational body 710 is located at a coupled position and the driven-side rotational body 710 is in a state coupled to the drive-side rotational body 110 .
- the state illustrated in FIG. 13B is brought about.
- the pin 860 is engaged with the side wall 732 of the helical groove 730 , thus locking the driven-side rotational body 120 against the urging force of the urging members 135 .
- the pin 860 is moved relatively in the groove 720 in a circumferential direction while being engaged with the side wall 732 of the helical groove 730 .
- the driven-side rotational body 710 is thus shifted from the coupled position to a decoupled position.
- the position of the pin 860 in the groove 720 is shifted relatively in a direction from the helical groove 730 toward the annular groove 740 .
- the engagement member 881 which is fixed to the locking member 850 together with the pin 860 , is shifted relative to the driven-side rotational body 710 .
- the engagement member 881 is in contact with the first surface 771 of the flange 770 .
- the engagement member 881 is permitted to tilt in the certain direction (the rightward direction as viewed in FIGS.
- the engagement member 881 is thus prevented from tilting even if the urging force of the urging members 135 acts on the driven-side rotational body 710 such that the engagement member 881 is pressed by the flange 770 . As a result, the engagement member 881 is held at the reference position, thus maintaining engagement between the engagement member 881 and the flange 770 . This restricts movement of the driven-side rotational body 710 from the decoupled position to the coupled position.
- the pin 860 is moved to the connecting portion of the annular groove 740 such that the pin 860 becomes separate from the side surface of the groove 720 (the side wall 741 of the annular groove 740 ), the one-way locking portion 880 restricts shifting of the driven-side rotational body 710 .
- the pin 860 is thus held in the annular groove 740 .
- the actuator 150 is operated to retract the pin 860 of the locking member 850 from the annular groove 740 of the groove 720 . This also causes disengagement between the engagement member 881 and the flange 770 .
- the driven-side rotational body 710 is thus moved to the coupled position by the urging force of the urging members 135 . As a result, the driven-side rotational body 710 and the drive-side rotational body 110 become coupled to each other, thus switching the clutch 800 to the engaged state.
- the fifth embodiment achieves advantages equivalent to the advantage (1) of the first embodiment and the advantage (6) of the fourth embodiment.
- the clutch according to the present disclosure is not restricted to the configurations illustrated in the above-described embodiments but may be embodied in, for example, the forms described below, which are modifications of the embodiments.
- the depth of the annular groove 420 is small in the vicinity of the starting end 421 relative to the depths of the other portions in the circumferential direction of the driven-side rotational body 120 .
- the depth of the helical groove 410 becomes gradually greater from the starting end 411 to the finishing end 412 .
- the depth of the annular groove or the depth of the helical groove may be uniform in the circumferential direction. That is, the step between the annular groove and the helical groove may be set to a uniform size in the circumferential direction of the driven-side rotational body 120 .
- the protrusion is formed over the entire length of the connecting portion of the groove.
- the opposite ends of the protrusion reach the non-connecting portion.
- shifting of the pin into the helical groove can be restrained by engaging the protrusion with the recess of the pin over the entire length of the connecting portion.
- the opposite ends of the protrusion thus do not necessarily have to reach the non-connecting portion. For example, only one of the end portions may reach the non-connecting portion.
- the length of the protrusion may be equal to the length of the connecting portion such that neither end portion reaches the non-connecting portion.
- the protrusion does not necessarily have to extend over the entire length of the connecting portion.
- the protrusion may be provided in a portion of the connecting portion of the groove.
- the recessed groove is formed over the entire length of the annular groove.
- the recessed groove only has to be formed at least over the entire length of the connecting portion of the annular groove. That is, if the protrusion is formed at least over the entire length of the connecting portion, shifting from the annular groove into the helical groove is restrained. Further, if shifting of the pin from the annular groove into the helical groove is restrained and disengagement of the clutch is restrained, the recessed groove may be formed in a portion of the connecting portion.
- the flange is formed over the entire circumference of the outer circumferential surface of the driven-side rotational body.
- the flange does not necessarily have to extend over the entire circumference but may be arranged in a portion of the outer circumferential surface to extend in the circumferential direction of the driven-side rotational body.
- the number of the urging members may be modified as needed.
- a single urging member may be employed to urge the driven-side rotational body.
- Any suitable urging member may be employed as long as the urging member urges the driven-side rotational body toward the coupled position.
- the urging member is thus not restricted to the aforementioned compression coil spring.
- a tension spring for pulling the driven-side rotational body toward the coupled position may be employed as the urging member.
- the actuator is not restricted to the self-holding type solenoid but may be, for example, a solenoid having a locking member that is inserted into a groove only when a coil is energized.
- the clutch is disengaged only when the coil is energized. The clutch is thus maintained in the engaged state if the coil cannot be energized. As a result, even when the actuator fails to operate normally, the pump can be operated.
- the actuator is not restricted to a solenoid. That is, any other suitable actuator than the solenoid, such as a hydraulic type actuator, may be used to selectively insert and retract the locking member. Also in this case, the clutch is disengaged through engagement between a groove of the driven-side rotational body and the locking member. The force needed to disengage the clutch is thus obtained from rotational force of the driven-side rotational body. As a result, disengagement is carried out by small force.
- the clutch is not restricted to the configuration in which drive force is transmitted through the balls.
- the clutch may be a pressing type clutch.
- opposed surfaces of the driven-side rotational body and the drive-side rotational body may be parallel tapered surfaces each inclined with respect to the axial direction.
- the tapered surfaces serve as pressing surfaces.
- the shapes of the components are not restricted particularly to the shapes of the illustrated embodiments, as long as the operation illustrated for each embodiment is ensured.
- ball accommodating grooves 927 may be formed in a large diameter portion 922 of a driven-side rotational body 910 and recesses 928 may be formed by lightening portions that lack the ball accommodating grooves 927 . This decreases the weight of the driven-side rotational body 910 and thus reduces the inertial force caused by the driven-side rotational body 910 . As a result, when the driven-side rotational body 910 reaches a decoupled position, rotation of the driven-side rotational body 910 quickly stops.
- the clutch switches the state of power transmission from the crankshaft to the pump.
- the clutch according to the present disclosure may be employed as a clutch arranged between other auxiliary devices, such as a compressor or an oil pump, and the crankshaft.
- the clutch according to the present disclosure is not restricted to the clutch for switching the state of power transmission from the crankshaft but may be used as a clutch for switching the state of power transmission from other drive sources.
Abstract
A clutch is provided with a drive-side rotational body and a driven-side rotational body, which is movable in the axial direction of the drive-side rotational body between a coupled position. The driven-side rotational body has a groove having a helical portion and an annular portion. The clutch also includes an urging member and a pin that is selectively inserted into and retracted from the groove. The clutch moves the driven-side rotational body to the decoupled position against the urging force of the urging member by inserting the pin in the helical portion. The clutch further includes a restricting portion that restricts shifting of the position of the pin from the annular portion to the helical portion when the pin is positioned in the annular portion.
Description
- The present disclosure relates to a clutch that switches the state of power transmission from a drive-side rotational body to a driven-side rotational body by switching the coupling state of the driven-side rotational body with respect to the drive-side rotational body.
- An engine is known that couples a mechanical pump, which circulates coolant, to the crankshaft through a clutch to operate the pump using rotational force of the crankshaft and disengages the clutch to stop operation of the pump. Clutches for switching the coupling state of the pump with respect to the crankshaft include a clutch having a drive-side rotational body coupled to the crankshaft and a driven-side rotational body, which is rotational relative to the drive-side rotational body. The clutch is maintained in the engaged state by pressing the rotational bodies against each other using magnetic force of magnets.
- Such clutches include a clutch described in
Patent Document 1. The clutch described inPatent Document 1 includes a coil. To disengage the clutch, energization control is performed on the coil to generate a magnetic field that cancels the aforementioned magnetic force. - Patent Document 1: Japanese Laid-Open Patent Publication No. 2010-203406
- Problems that the Invention is to Solve
- In a configuration in which the clutch is maintained in the engaged state by pressing the drive-side rotational body and the driven-side rotational body against each other as described in
Patent Document 1, the force needed for such pressing becomes greater as the torque that needs to be transmitted through the clutch, or, in other words, the torque needed by an auxiliary device driven and rotated by the driven-side rotational body, becomes greater. To increase the pressing force, magnets with a greater magnetic force must be employed. This necessitates a larger-sized coil to cancel the magnetic force. - The larger-sized coil enlarges the size of the clutch and increases power consumption. Therefore, the force needed for disengagement is therefore desired to be minimized while ensuring transmission of great torque.
- This problem is not restricted to clutches that cancel magnetic force of magnets by generating a magnetic field as in the above-described case. The same problem is generally present in clutches that are disengaged by causing relative movement between a drive-side rotational body and a driven-side rotational body with an actuator, such as clutches that are disengaged using hydraulic pressure.
- Accordingly, it is an objective of the present disclosure to provide a clutch that can be disengaged by a small force.
- To achieve the foregoing objective and in accordance with one aspect of the present invention, a clutch is provided that includes a drive-side rotational body, a driven-side rotational body, an urging member, a groove, a pin, and a restricting portion. The driven-side rotational body is movable in an axial direction of the drive-side rotational body between a coupled position at which the driven-side rotational body is coupled to the drive-side rotational body and a decoupled position at which the driven-side rotational body is decoupled from the drive-side rotational body. The urging member urges the driven-side rotational body from the decoupled position toward the coupled position. The groove is formed in an outer circumferential surface of the driven-side rotational body. The groove has a helical portion that extends about an axis of the driven-side rotational body and an annular portion that is formed continuously from the helical portion and extends over an entire circumference of the driven-side rotational body and perpendicularly to the axial direction. The pin is selectively inserted into and retracted from the groove and restricted from moving in the axial direction. When the pin is in a state inserted in the helical portion and engaged with a side wall of the helical portion, the position of the pin is shifted from the helical portion to the annular portion through rotation of the driven-side rotational body such that the driven-side rotational body is moved to the decoupled position against urging force of the urging member. The restricting portion restricts shifting of the position of the pin from the annular portion to the helical portion when the pin is in a state located in the annular portion.
-
FIG. 1 is a cross-sectional view showing a clutch according to a first embodiment; -
FIG. 2 is a side view showing the clutch shown inFIG. 1 in a disengaged state; -
FIG. 3 is a side view showing the clutch ofFIG. 1 in an engaged state; -
FIG. 4 is a cross-sectional view illustrating the relationship between a groove of a driven-side rotational body and a stopper member and the configuration of an actuator for operating the stopper member; -
FIG. 5 is a side view showing a clutch according to a second embodiment in a disengaged state; -
FIG. 6 is a side view showing the clutch illustrated inFIG. 5 in an engaged state; -
FIG. 7 is a developed view showing a groove of the clutch ofFIG. 5 ; -
FIG. 8 is a side view showing a clutch according to a third embodiment in a disengaged state; -
FIG. 9 is a side view showing the clutch illustrated inFIG. 8 in an engaged state; -
FIG. 10 is a developed view showing a groove of the clutch ofFIG. 8 ; -
FIG. 11 is a developed view showing a groove of a modification of the third embodiment; -
FIGS. 12A , 12B, 12C, and 12D are schematic diagrams illustrating change of the state of a clutch according to a fourth embodiment; -
FIGS. 13A , 13B, 13C, and 13D are schematic diagrams illustrating change of the state of a clutch according to a fifth embodiment; and -
FIG. 14 is a perspective view showing a driven-side rotational body according to another embodiment. - A clutch according to a first embodiment will now be described with reference to
FIGS. 1 to 4 . - A clutch according to a first embodiment switches the state of power transmission from a crankshaft arranged in an engine to a water pump, which circulates coolant of the engine.
- As shown in
FIG. 1 , aclutch 100 of the first embodiment is accommodated in anaccommodating portion 310, which is arranged in ahousing 300. A substantiallycylindrical support member 320 is fitted in thehousing 300. Anoutput shaft 210 of theclutch 100 is rotationally supported by thesupport member 320 through a first bearing 330, which is located at an inner circumferential side of thesupport member 320. - An
impeller 220 of apump 200 is attached to a distal end portion (a right end portion as viewed inFIG. 1 ) of theoutput shaft 210 in a manner rotational integrally with theoutput shaft 210. A drive-siderotational body 110 is rotationally supported by a proximal end portion (a left end portion as viewed in the drawing) of theoutput shaft 210 through a second bearing 340. Astraight spline 212 is formed in an outer circumferential surface of a portion of theoutput shaft 210 between the first bearing 330 and the second bearing 340. - With reference to
FIG. 1 , a driven-siderotational body 120 is arranged between thehousing 300 and the drive-siderotational body 110. Anengagement portion 121, which is meshed with thestraight spline 212 of theoutput shaft 210, is formed in an inner circumferential surface of the driven-siderotational body 120. This configuration allows the driven-siderotational body 120 to rotate integrally with theoutput shaft 210 and move in the axial direction of theoutput shaft 210. In the first embodiment, as represented by the long dashed short dashed lines inFIGS. 1 to 3 , theoutput shaft 210, the drive-siderotational body 110, and the driven-siderotational body 120 are arranged coaxially with one another. Hereinafter, the extending direction of the axis of these components will be referred to as the axial direction. - The driven-side
rotational body 120 has an outline including two columns that have different diameters and are joined coaxially with each other. The driven-siderotational body 120 is supported by theoutput shaft 210 in such an orientation that alarge diameter portion 122 is located on the side close to the drive-side rotational body 110 (a left side as viewed inFIG. 1 ) and asmall diameter portion 123 is arranged on the side close to the pump 200 (a right side as viewed in the drawing). - A
recess 124 having an opening facing thepump 200 is formed in thesmall diameter portion 123 of the driven-siderotational body 120. A plurality ofaccommodating recesses 125 for accommodatingurging members 135 are formed in a bottom portion of therecess 124. Theaccommodating recesses 125 are arranged circumferentially in a manner surrounding theoutput shaft 210. - Each of the urging
members 135 is, for example, a coil spring and accommodated in the corresponding one of theaccommodating recesses 125. Each urgingmember 135 has a distal end secured to a securingprojection 211, which projects from theoutput shaft 210. The urgingmembers 135 are accommodated in the correspondingaccommodating recesses 125 each in a compressed state and urge the driven-siderotational body 120 toward the drive-side rotational body 110 (leftward as viewed inFIG. 1 ). - A plurality of
ball accommodating grooves 127 each for accommodating a corresponding one ofballs 130 are formed in thelarge diameter portion 122 of the driven-siderotational body 120 and arranged circumferentially. Anarcuate groove 111, which extends over the entire circumference of an inner circumferential surface of the drive-siderotational body 110, is formed in the inner circumferential surface of the drive-siderotational body 110. With reference toFIG. 1 , thearcuate groove 111 has an arcuate cross section. Each of theballs 130 is accommodated in the space formed by the corresponding one of theball accommodating grooves 127 and thearcuate groove 111. - When the driven-side
rotational body 120 is arranged at the position illustrated inFIG. 1 after having been moved toward the drive-siderotational body 110 by the urging force of the urgingmembers 135, the drive-siderotational body 110 and the driven-siderotational body 120 are coupled to each other through theballs 130. - Hereinafter, out of axial positions of the driven-side
rotational body 120 moving axially along theoutput shaft 210, the position at which the drive-siderotational body 110 and the driven-siderotational body 120 are coupled to each other, as illustrated inFIG. 1 , will be referred to as a coupled position. - A cup-like driven-
side pulley 270, which surrounds the clutch 100 accommodated in theaccommodating portion 310 of thehousing 300, is attached to the drive-siderotational body 110. A drive-side pulley 260 is attached to an end portion of thecrankshaft 250 in a manner rotational integrally with thecrankshaft 250. The drive-side pulley 260 and the driven-side pulley 270 are coupled to each other through abelt 280, which is looped over the drive-side pulley 260 and the driven-side pulley 270. - As a result, as illustrated in
FIG. 1 , when the driven-siderotational body 120 is arranged at the coupled position and the drive-siderotational body 110 and the driven-siderotational body 120 are coupled to each other through theballs 130, rotation of thecrankshaft 250 is transmitted to the driven-siderotational body 120 and theoutput shaft 210 via the drive-side pulley 260 and thebelt 280. This causes theimpeller 220, which rotates integrally with theoutput shaft 210, to supply coolant out from thepump 200. As represented by the arrows inFIGS. 2 and 3 , the drive-siderotational body 110 rotates in a clockwise direction as viewed from the side corresponding to the distal end of the output shaft 210 (the side corresponding to the right end as viewed inFIGS. 2 and 3 ) toward the drive-siderotational body 110. - Referring to
FIGS. 2 and 3 , each of theball accommodating grooves 127, which are formed in thelarge diameter portion 122 of the driven-siderotational body 120, extends in the axial direction from an end surface of thelarge diameter portion 122 before being curved and then extends in the rotational direction of the drive-siderotational body 110. A finishing end of eachball accommodating groove 127 forms a holdingportion 128. - The depth of each
ball accommodating groove 127 becomes smaller in the rotational direction of the drive-siderotational body 110 such that the depth of the holdingportion 128 is minimized. - As a result, as illustrated in
FIG. 2 , when eachball 130 is accommodated in the axially extended portion of the correspondingball accommodating groove 127, a clearance in which theball 130 is permitted to rotate, together with the driven-siderotational body 120, with respect to the drive-siderotational body 110 is formed between theball accommodating groove 127 and the arcuate groove 111 (seeFIG. 1 ) of the drive-siderotational body 110. - In contrast, as illustrated in
FIG. 3 , when eachball 130 is located in the corresponding holdingportion 128 after having been moved in theball accommodating groove 127, the clearance between the holdingportion 128 and the arcuate groove 111 (seeFIG. 1 ) of the drive-siderotational body 110 is small. Theball 130 is thus caught between the driven-siderotational body 120 and the drive-siderotational body 110. This restricts rotation of theball 130 together with the driven-siderotational body 120 with respect to the drive-siderotational body 110. - In this manner, the
balls 130 are non-rotational when the driven-siderotational body 120 is arranged at the coupled position illustrated inFIG. 3 . This allows the driven-siderotational body 120 to rotate together with the drive-siderotational body 110. That is, when the driven-siderotational body 120 is located at the coupled position, theballs 130 are caught between the driven-siderotational body 120 and the drive-siderotational body 110 in a non-rotational manner, thus coupling the driven-siderotational body 120 to the drive-siderotational body 110. - In contrast, when the driven-side
rotational body 120 is arranged at the position illustrated inFIG. 2 , theballs 130 are released from the holdingportions 128 and received in the axially extended portions of the correspondingball accommodating grooves 127. Specifically, a substantially half of eachball 130 is accommodated in thearcuate groove 111 of the drive-siderotational body 110. This restricts axial movement of theball 130 relative to the drive-siderotational body 110. When eachball 130 is received in the axially extended portion, which has a depth greater than the depth of each holdingportion 128, after having been released from the holdingportion 128 with a smaller depth, theball 130 is released from the driven-siderotational body 120 and the drive-siderotational body 110. As a result, the drive-siderotational body 110 and the driven-siderotational body 120 are allowed to rotate relative to each other. That is, the driven-siderotational body 120 is decoupled from the drive-siderotational body 110. - Hereinafter, out of the axial positions of the driven-side
rotational body 120 moving axially along theoutput shaft 210, the position at which the drive-siderotational body 110 and the driven-siderotational body 120 are decoupled from each other as illustrated inFIG. 2 will be referred to as a decoupled position. - As illustrated in
FIG. 2 , acircumferential groove 400 is formed in an outer circumferential surface of thesmall diameter portion 123 of the driven-siderotational body 120. Thegroove 400 includes ahelical groove 410 serving as a helical portion extending about the axis in a manner inclined with respect to the axial direction and anannular groove 420 serving as an annular portion extending perpendicular to the axial direction. Thehelical groove 410 extends in a manner revolving on the outer circumferential surface of the driven-siderotational body 120 by one cycle and inclined such that thehelical groove 410 approaches the drive-siderotational body 110 toward the trailing end in the rotational direction of the drive-siderotational body 110. Theannular groove 420 is formed continuously from thehelical groove 410 and extends over the entire circumference of the outer circumferential surface of the driven-siderotational body 120. The configuration of thegroove 400 will be described in detail below. - With reference to
FIGS. 2 and 3 , the clutch 100 includes a lockingmember 140 and anactuator 150 for selectively inserting and retracting apin 141, which is arranged at the distal end of the lockingmember 140, with respect to thegroove 400. The axial position of the lockingmember 140 is restricted. As illustrated inFIG. 3 , the axial position of the lockingmember 140 is set such that thepin 141 is inserted into a portion of thehelical groove 410 of thegroove 400 in the vicinity of a startingend 411 when the driven-siderotational body 120 is arranged at the coupled position. If the lockingmember 140 is operated by theactuator 150 to move toward the driven-siderotational body 120 when the driven-siderotational body 120 is located at the coupled position, thepin 141 is inserted into the portion of thehelical groove 410 in the vicinity of the startingend 411. After having been inserted into thehelical groove 410, thepin 141 is engaged with aside wall 413 of thehelical groove 410, thus locking the driven-siderotational body 120 against the urging force of the urgingmembers 135. - If the
pin 141 of the lockingmember 140 is inserted into thehelical groove 410 when the driven-siderotational body 120 is coupled to the drive-siderotational body 110, the driven-siderotational body 120 is rotated with thepin 141 engaged with theside wall 413 of thehelical groove 410. Then, while thepin 141 slides on theside wall 413 of thehelical groove 410, the driven-siderotational body 120 moves axially from the coupled position toward the decoupled position. When thepin 141 reaches a finishingend 412 of thehelical groove 410, thepin 141 is inserted into theannular groove 420 and the driven-siderotational body 120 is switched from the coupled position to the decoupled position. As has been described, the clutch 100 is configured such that, by inserting thepin 141 of the lookingmember 140 into thegroove 400 to engage thepin 141 with theside wall 413 of thehelical groove 410, the driven-siderotational body 120 is moved to the decoupled position against the urging force of the urgingmembers 135. - When the drive-side
rotational body 110 and the driven-siderotational body 120 are decoupled from each other, torque transmission from the drive-siderotational body 110 to the driven-siderotational body 120 is stopped. However, immediately after such decoupling, the driven-siderotational body 120 is continuously rotated by inertial force. Specifically, when the driven-siderotational body 120 is located at the decoupled position, thepin 141 is inserted in theannular groove 420, which extends over the entire circumference of the driven-siderotational body 120. The driven-siderotational body 120 is thus prohibited from shifting axially. In this state, since torque transmission from the drive-siderotational body 110 to the driven-siderotational body 120 is stopped, the rotational speed of the driven-siderotational body 120 gradually decreases and such rotation eventually stops. - The driven-side
rotational body 120 is urged toward the coupled position by the urging force of the urgingmembers 135. Accordingly, to maintain the decoupled state, thepin 141 of the lockingmember 140 must be maintained in a state inserted in theannular groove 420 of the driven-siderotational body 120. To re-couple the drive-siderotational body 110 and the driven-siderotational body 120 to each other, thepin 141 is retracted from theannular groove 420 of thegroove 400 by means of theactuator 150. After thepin 141 is retracted in this manner, the lockingmember 140 is disengaged from the driven-siderotational body 120 and the driven-siderotational body 120 is moved to the coupled position by the urging force of the urgingmembers 135. As a result, the drive-siderotational body 110 and the driven-siderotational body 120 are returned to the coupled state. - In the
groove 400 formed in the outer circumferential surface of the driven-siderotational body 120, theannular groove 420 is formed continuously from thehelical groove 410 and extends over the entire circumference of the outer circumferential surface of the driven-siderotational body 120. Thegroove 400 of the driven-siderotational body 120 thus has a connecting portion at which theannular groove 420 and thehelical groove 410 are connected to each other. Therefore, when thepin 141 is inserted in theannular groove 420 such that the driven-siderotational body 120 is located at the decoupled position but the driven-siderotational body 120 is continuously rotated by inertial force, thepin 141 is possibly shifted to thehelical groove 410 through the connecting portion between thehelical groove 410 and theannular groove 420. To avoid this, the clutch 100 of the first embodiment includes a restricting portion, which restricts such shifting of thepin 141 from theannular groove 420 to thehelical groove 410 when thepin 141 is inserted in theannular groove 420. - The restricting portion is configured in the manner described below. That is, in the
groove 400, as illustrated inFIGS. 2 to 4 , theannular groove 420 has a depth greater than the depth of thehelical groove 410. In other words, the bottom surface of theannular groove 420 is located radially inward of the bottom surface of thehelical groove 410. Theannular groove 420 and thehelical groove 410 are thus connected together with a step formed between theannular groove 420 and thehelical groove 410. In the first embodiment, the step, which is theside wall 423 of theannular groove 420, functions as the restricting portion. - With reference to
FIGS. 2 and 3 , the width of thehelical groove 410 becomes gradually smaller from the startingend 411 to the finishingend 412. Therefore, when the inserting position of thepin 141, which has been inserted into the portion of thehelical groove 410 in the vicinity of the startingend 411, reaches the finishingend 412 of thehelical groove 410 as the driven-siderotational body 120 rotates, thepin 141 is pressed by theside wall 413 of thehelical groove 410 and thus inserted into theannular groove 420, which has a depth greater than the depth of thehelical groove 410. - Further, as illustrated in
FIG. 4 , the depth of thehelical groove 410 becomes gradually greater from the startingend 411 to the finishingend 412. In other words, the radial position of the bottom surface of thehelical groove 410 approaches the axis of the driven-siderotational body 120 gradually from the startingend 411 to the finishingend 412. The depth of theannular groove 420 is small at the startingend 421 of theannular groove 420, which corresponds to the finishingend 412 of thehelical groove 410, relative to the depths of the other portions in the circumferential direction of the driven-siderotational body 120. The radial distance between the bottom surface of theannular groove 420 and the bottom surface of thehelical groove 410 is thus small at the portion corresponding to the finishingend 412 of thehelical groove 410 and the startingend 421 of theannular groove 420, relative to other portions. That is, at this portion, the step between thehelical groove 410 and theannular groove 420 is relatively small. This attenuates impact applied to thepin 141 when thepin 141 reaches the finishingend 412 of thehelical groove 410 and is then inserted into theannular groove 420, which has a depth greater than the depth of thehelical groove 410, compared to a case in which the size of the step is set uniform in the circumferential direction. Specifically, the step at the aforementioned portion is set to such a size that the aforementioned impact is attenuated and shifting of thepin 141 from theannular groove 420 to thehelical groove 410 is restrained. - The structure of the
actuator 150 will now be described. - As illustrated in
FIG. 4 , theactuator 150 of the first embodiment is an electromagnetic actuator, which is operated through action of a magnetic field generated by energizing acoil 153 accommodated in afirst case 152. - The
first case 152 has a cylindrical shape having a bottom portion and a fixedcore 154 is fixed to the bottom portion. Thecoil 153 is arranged in thefirst case 152 to surround the fixedcore 154. That is, in theactuator 150, the fixedcore 154 and thecoil 153 configure an electromagnet. Amovable core 155 is movably accommodated in thecoil 153 of thefirst case 152 at a position facing the fixedcore 154. The fixedcore 154 and themovable core 155 of the first embodiment are both iron cores. - A cylindrical
second case 158 is fixed to a distal end portion (a right end portion as viewed inFIG. 4 ) of thefirst case 152. Apermanent magnet 159 is fixed to an end portion of thesecond case 158 fixed to thefirst case 152 in a manner surrounding themovable core 155. As has been described, themovable core 155 is accommodated in thefirst case 152 such that a proximal end zone (a left end zone as viewed inFIG. 4 ) of themovable core 155 faces the fixedcore 154. A distal end zone (a right end zone as viewed in the drawing) projects outward from thesecond case 158. - A
ring member 160 is attached to the portion of themovable core 155 that is accommodated in thesecond case 158. Acoil spring 161, which has an end secured to thesecond case 158 and an opposite end secured to thering member 160, is accommodated in thesecond case 158 in a compressed state. - The
coil spring 161 urges themovable core 155 in the direction in which themovable core 155 projects from the second case 158 (rightward as viewed inFIG. 4 ). The portion of themovable core 155 that projects from thesecond case 158 is coupled to the lockingmember 140 through a fixingpin 162. - The locking
member 140 is pivotally coupled to themovable core 155 at the proximal end of the lockingmember 140 and pivotally supported by apivot shaft 156. This allows the lockingmember 140 to pivot about thepivot shaft 156, which is a support point of pivot, when themovable core 155 moves. As a result, as represented by the solid lines inFIG. 4 , as the extent of projection of themovable core 155 from thesecond case 158 is increased by the urging force of thecoil spring 161, thepin 141 of the lockingmember 140 is inserted sequentially into thehelical groove 410 and theannular groove 420 of the driven-siderotational body 120. - If the
coil 153 is energized in this state, a magnetic field is generated through such energization to magnetize the fixedcore 154 and themovable core 155. Themovable core 155 is thus attracted to the fixedcore 154 against the urging force of thecoil spring 161. The direction of the magnetic field generated by thecoil 153 at this stage matches with the direction of the magnetic field generated by thepermanent magnet 159. - As the
movable core 155 is attracted and moved toward the fixed core 154 (leftward as viewed inFIG. 4 ), the lockingmember 140 is pivoted clockwise as viewed inFIG. 4 to retract the distal end of the lockingmember 140 from thegroove 400. That is, theactuator 150 retracts the lockingmember 140 from thegroove 400 by attracting themovable core 155 using magnetic force produced through energization of thecoil 153. - After the
movable core 155 is attracted and moved to a contact position at which themovable core 155 contacts the fixed core 154 (the position represented by the long dashed double-short dashed lines inFIG. 4 ), themovable core 155 is held in contact with the fixedcore 154 by the magnetic force of thepermanent magnet 159 even if the energization is stopped afterwards. - In contrast, if the
coil 153 is energized by an electric current flowing in the opposite direction to the direction of the electric current for attracting themovable core 155 when themovable core 155 is arranged at the contact position represented by the long dashed double-short dashed lines inFIG. 4 , a magnetic field is generated in the opposite direction to the direction of the magnetic field of thepermanent magnet 159. This attenuates the attracting force of thepermanent magnet 159, and themovable core 155 is separated from the fixedcore 154 by the urging force of thecoil spring 161. Themovable core 155 then moves to the projected position represented by the solid lines inFIG. 4 . As themovable core 155 is moved from the contact position to the projected position, the lockingmember 140 is pivoted counterclockwise as viewed inFIG. 4 and thepin 141 of the lockingmember 140 is inserted into thegroove 400. - When the
movable core 155 is located at the projected position at which themovable core 155 is separated from the fixedcore 154, the urging force of thecoil spring 161 exceeds the attracting force of thepermanent magnet 159. As a result, if thecoil 153 is energized to separate themovable core 155 from the fixedcore 154, themovable core 155 is held at the projected position even after such energization is stopped afterward. - That is, the
actuator 150 of the first embodiment is a self-holding type solenoid, which switches the engagement state of the clutch 100 by applying direct electric currents in different directions and thus moving themovable core 155 and does not need the energization to maintain the clutch 100 in either the engaged state or the disengaged state. - Operation of the clutch 100 according to the present embodiment will now be described.
- As represented by the long dashed double-short dashed lines in
FIG. 4 , when themovable core 155 of theactuator 150 is arranged at the contact position, thepin 141 of the lockingmember 140 is located in the exterior of thegroove 400. At this stage, the driven-siderotational body 120 is held at the coupled position by the urging force of the urgingmembers 135 such that the clutch 100 is in the engaged state. That is, the clutch 100 transmits rotation of the drive-siderotational body 110 to theoutput shaft 210. - If, in this state, the
coil 153 of theactuator 150 is energized to generate a magnetic field in the opposite direction to the direction of the magnetic field of thepermanent magnet 159, themovable core 155 is moved from the contact position to the projected position represented by the solid lines inFIG. 4 by the urging force of thecoil spring 161. This pivots the lockingmember 140 counterclockwise as viewed inFIG. 4 , thus inserting thepin 141 of the lockingmember 140 into the portion of thehelical groove 410 of thegroove 400 of the driven-side rotational body in the vicinity of the startingend 411. The driven-siderotational body 120 is thus stopped and held in the state illustrated inFIG. 3 . - When the driven-side
rotational body 120 is rotated together with the drive-siderotational body 110 with thepin 141 locking the driven-siderotational body 120 and thepin 141 is moved relatively in thehelical groove 410, the driven-siderotational body 120 is moved from the coupled position to the decoupled position and thus switched from the state illustrated inFIG. 3 to the state illustrated inFIG. 2 . In this manner, thepin 141 is switched to a state inserted in theannular groove 420 and the driven-siderotational body 120 reaches the decoupled position. This stops transmission of rotation of the drive-siderotational body 110 to the driven-siderotational body 120, thus disengaging the clutch 100. - Immediately after the driven-side
rotational body 120 and the drive-siderotational body 110 are disengaged from each other, the driven-siderotational body 120 is continuously rotated by inertial force while receiving action of friction force produced between the driven-siderotational body 120 and thepin 141, which is inserted in theannular groove 420 as shown inFIG. 2 . When thepin 141 is inserted in theannular groove 420 and the driven-siderotational body 120 is rotating, thepin 141 is engaged with the step in the boundary between thehelical groove 410 and theannular groove 420, which is theside wall 423 of theannular groove 420. Therefore, unless thepin 141 is shifted to be retracted from theannular groove 420 and thus move past the step, thepin 141 cannot be shifted into thehelical groove 410, so that shifting of thepin 141 from theannular groove 420 into thehelical groove 410 is restricted. In this manner, the driven-siderotational body 120 is rotated with thepin 141 of the lockingmember 140 inserted in theannular groove 420 of the driven-siderotational body 120. The rotational speed of the driven-siderotational body 120 then decreases gradually until the driven-siderotational body 120 eventually stops rotating. - To switch the clutch 100 from the disengaged state to the engaged state, the
coil 153 of theactuator 150 is energized to generate a magnetic field in the same direction as the direction of the magnetic field of thepermanent magnet 159. Themovable core 155 is thus attracted toward the fixedcore 154 by magnetic force produced by energization and moved from the projected position represented by the solid lines inFIG. 4 to the contact position represented by the long dashed double-short dashed lines in the drawing. This pivots the lockingmember 140 clockwise as viewed inFIG. 4 , thus fully retracting thepin 141 of the lockingmember 140 from thegroove 400. - After having been released from the locking
member 140, the driven-siderotational body 120 is moved to the coupled position by the urging force of the urgingmembers 135. The driven-siderotational body 120 and the drive-siderotational body 110 thus become coupled to each other, switching the clutch 100 to the engaged state. - The above described embodiment provides the following advantages.
- (1) In the first embodiment, when the
pin 141 of the lockingmember 140 is inserted in the helical portion of the driven-siderotational body 120, the driven-siderotational body 120 is rotated with thepin 141 engaged with theside wall 413 of the helical portion. This moves the driven-siderotational body 120 from the coupled position to the decoupled position against the urging force of the urgingmembers 135. In this manner, the force needed to disengage the clutch 100 is obtained from the rotational force of the driven-siderotational body 120. As a result, the drive-siderotational body 110 and the driven-siderotational body 120 are disengaged from each other by small force. - (2) In the first embodiment, when the
pin 141 is inserted in theannular groove 420, thepin 141 is engaged with theside wall 423 at the step in the boundary between thehelical groove 410 and theannular groove 420. Therefore, unless thepin 141 is shifted to be retracted from theannular groove 420 and moves past the step, thepin 141 cannot be shifted to thehelical groove 410. That is, when thepin 141 is inserted in theannular groove 420, theside wall 423 at the step in the boundary between thehelical groove 410 and theannular groove 420 functions as a restricting portion. This restricts shifting of thepin 141 from theannular groove 420 to thehelical groove 410, thus restraining shifting of the driven-siderotational body 120 to the coupled position despite the fact that thepin 141 is maintained in thegroove 400. - (3) In the first embodiment, the depth of the
annular groove 420 is small in the vicinity of the startingend 421 relative to the depths of the other portions in the circumferential direction of the driven-siderotational body 120. The depth of thehelical groove 410 becomes gradually greater from the startingend 411 to the finishingend 412. The step between the finishingend 412 of thehelical groove 410 and the startingend 421 of theannular groove 420 is small-sized relative to steps in other portions. This attenuates impact applied to thepin 141 when thepin 141 is moved from thehelical groove 410 and inserted into theannular groove 420, the depth of which is greater than the depth of thehelical groove 410, compared to a case in which the step between theannular groove 420 and thehelical groove 410 is set to a uniform size in the circumferential direction of the driven-siderotational body 120. - A clutch according to a second embodiment will now be described with reference to
FIGS. 5 to 7 . - As illustrated in
FIG. 5 , a clutch 500 of the second embodiment is different from the first embodiment in terms of the configuration of agroove 520 formed in an outer circumferential surface of asmall diameter portion 511 of a driven-siderotational body 510 and the configuration of apin 560 of a lockingmember 550. The remainder of the configuration is the same as those of the first embodiment. Thus, like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted. - In the second embodiment, the
groove 520 of the driven-siderotational body 510 has ahelical groove 530 inclined with respect to the axial direction and anannular groove 540, which is formed continuously from thehelical groove 530 and extends over the entire circumference of an outer circumferential surface of the driven-siderotational body 510 and perpendicularly to the axial direction. - With reference to
FIGS. 5 to 7 , theannular groove 540 has a connectingportion 541, which has a depth equal to the depth of thehelical groove 530 and is connected to thehelical groove 530, and anon-connecting portion 542, which is disconnected from thehelical groove 530. InFIGS. 5 to 7 , the boundary between the connectingportion 541 of theannular groove 540 and thehelical groove 530 is represented by the long dashed double-short dashed line. The long dashed double-short dashed line representing the boundary coincides with the extended line of aside wall 544 of thenon-connecting portion 542 of theannular groove 540. - A
protrusion 543, which protrudes from the bottom surface of theannular groove 540 and extends in the extending direction of theannular groove 540, is formed in theannular groove 540. Theprotrusion 543 is formed over the entire length of the connectingportion 541. The opposite ends of theprotrusion 543 are arranged in thenon-connecting portion 542. Theprotrusion 543 of theannular groove 540 has a uniform width and is inclined with respect to the axial direction of the driven-siderotational body 510 by the inclination angle equal to the inclination angle of aside wall 531 of thehelical groove 530. As a result, with reference toFIG. 7 , the distance from theside wall 531 of thehelical groove 530 to theprotrusion 543 is a uniform distance d1 in the circumferential direction of the driven-siderotational body 510. - As shown in
FIGS. 5 to 7 , arecess 561, into which theprotrusion 543 can proceed, is formed at the distal end of thepin 560 of the lockingmember 550. InFIG. 7 , states of relative movement of thepin 560 of the lockingmember 550 in thegroove 520 when the driven-siderotational body 510 is in a rotating state are illustrated by way ofpins 560 represented by the long dashed double-short dashed lines. In the second embodiment, theprotrusion 543, which projects from the bottom surface of theannular groove 540, and therecess 561 of thepin 560 configure a restricting portion. - Referring to
FIG. 7 , the width d2 of thepin 560 of the lockingmember 550 is slightly smaller than the distance d1 from theside wall 531 of thehelical groove 530 to theprotrusion 543. The distance d3 from a starting end of theprotrusion 543, which is the end portion of theprotrusion 543 that thepin 560 reaches first when the driven-siderotational body 510 is rotated, to theside wall 544 of theannular groove 540 is substantially equal to but slightly greater than the length d4 from the side surface of thepin 560 to therecess 561. The width d5 of therecess 561 is greater than the width d6 of theprotrusion 543. - Operation of the present embodiment will now be described.
- As illustrated in
FIG. 6 , when the driven-siderotational body 510 is in a state coupled to the drive-siderotational body 110, theactuator 150 is operated to insert thepin 560 of the lockingmember 550 into a startingend 532 of thehelical groove 530 of thegroove 520. This engages thepin 560 with theside wall 531 of thehelical groove 530 to locks the driven-siderotational body 120 against the urging force of the urgingmembers 135. Then, as the driven-siderotational body 510 is rotated, thepin 560 is moved relatively in thegroove 520 in a circumferential direction while being engaged with theside wall 531 of thehelical groove 530. The width d2 of thepin 560 is slightly smaller than the distance d1 from theside wall 531 of thehelical groove 530 to theprotrusion 543. This restrains interference of theprotrusion 543 with movement of thepin 560 when thepin 560 is engaged with theside wall 531 of thehelical groove 530 and moved relatively in thegroove 520, thus allowing relative movement of thepin 560 in thehelical groove 530. Thepin 560 thus reaches theannular groove 540 and is then moved relatively in theannular groove 540 of thegroove 520 as the driven-siderotational body 510 is rotated. The driven-siderotational body 510 is rotated by inertial force at the decoupled position. - As has been described, the distance d3 from the starting end of the
protrusion 543 to theside wall 544 of theannular groove 540 is substantially equal to but slightly greater than the length d4 from the side wall of thepin 560 to therecess 561. The width d5 of therecess 561 is greater than the width d6 of theprotrusion 543. Therefore, when the driven-siderotational body 510 is rotated and thepin 560 is moved relatively in theannular groove 540 to reach the starting end of theprotrusion 543, which is arranged in theannular groove 540, theprotrusion 543 proceeds into therecess 561 and becomes engaged with therecess 561. Theprotrusion 543 extends in the extending direction of theannular groove 540 and is formed over the entire length of the connectingportion 541. As a result, even if the driven-siderotational body 510 is rotated by inertial force and thepin 560 is moved to the connectingportion 541 of theannular groove 540 such that thepin 560 and the side surface of thegroove 520, which is theside wall 544 of theannular groove 540 corresponding to thenon-connecting portion 542, become separate from each other, thepin 560 is engaged with theprotrusion 543 and thus held in theannular groove 540. - To switch the clutch 500 from the disengaged state to the engaged state, the
actuator 150 is operated to retract thepin 560 of the lockingmember 550 from theannular groove 540 of thegroove 520. This also causes disengagement between therecess 561 of thepin 560 and theprotrusion 543 of theannular groove 540. By retracting thepin 560 of the lockingmember 550 from thegroove 520 in this manner, the driven-siderotational body 510 is moved to the coupled position by the urging force of the urgingmembers 135. The driven-siderotational body 510 and the drive-siderotational body 110 thus become coupled to each other, switching the clutch 500 to the engaged state. - The second embodiment achieves the following advantage (4) as well as an advantage equivalent to the advantage (1) of the first embodiment.
- (4) In the second embodiment, shifting of the
pin 560 from theannular groove 540 to thehelical groove 530 is restricted unless thepin 560 is shifted to be retracted from theannular groove 540 and therecess 561 of thepin 560 and theprotrusion 543 of theannular groove 540 are disengaged from each other. That is, when thepin 560 is inserted in theannular groove 540, therecess 561 of thepin 560 and theprotrusion 543 of theannular groove 540 function as a restricting portion. Therefore, since shifting of thepin 560 from theannular groove 540 to thehelical groove 530 is restricted, it is possible to restrain shifting of the driven-siderotational body 510 to the coupled position despite the fact that thepin 560 is maintained in thegroove 520. - A clutch according to a third embodiment will now be described with reference to
FIGS. 8 to 10 . - As illustrated in
FIG. 8 , a clutch 600 of the third embodiment is different from the illustrated embodiments in terms of the configuration of agroove 620 formed in an outer circumferential surface of asmall diameter portion 611 of a driven-side rotational body 610 and the configuration of apin 660 of a lockingmember 650. The remainder of the configuration is the same as those of the first embodiment. Thus, like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted. - In the third embodiment, the
groove 620 of the driven-side rotational body 610 has ahelical groove 630 inclined with respect to the axial direction and anannular groove 640, which is formed continuously from thehelical groove 630 and extends over the entire circumference of an outer circumferential surface of the driven-side rotational body 610 and perpendicularly to the axial direction. - As illustrated in
FIGS. 8 to 10 , theannular groove 640 has a connectingportion 641, which has a depth equal to the depth of thehelical groove 630 and is connected directly to thehelical groove 630, and anon-connecting portion 642, which is not connected directly to thehelical groove 630. InFIGS. 8 to 10 , the boundary between the connectingportion 641 of theannular groove 640 and thehelical groove 630 is represented by the long dashed double-short dashed line. The long dashed double-short dashed line representing the boundary coincides with the extended line of aside wall 644 of thenon-connecting portion 642 of theannular groove 640. - A recessed
groove 643, which extends in the extending direction of theannular groove 640, is formed in theannular groove 640. Specifically, the recessedgroove 643 extends in a direction perpendicular to the axial direction of the driven-side rotational body 610. Also, the recessedgroove 643 extends over the entire length of theannular groove 640. That is, the recessedgroove 643 is formed over the entire circumference of the outer circumferential surface of the driven-side rotational body 610. - With reference to
FIGS. 8 to 10 , aprojection 661, which can be inserted into the recessedgroove 643, projects from the distal end of thepin 660 of the lockingmember 650. InFIG. 10 , states of relative movement of thepin 660 of the lockingmember 650 in thegroove 620 when the driven-side rotational body 610 is in a rotating state are illustrated bypins 660 represented by the long dashed double-short dashed lines. In the third embodiment, the recessedgroove 643, which is formed in the bottom surface of theannular groove 640, and theprojection 661 of thepin 660 configure a restricting portion. - Referring to
FIG. 10 , the length d1 from the side surface of thepin 660 of the lockingmember 650 to theprojection 661 is substantially equal to but slightly greater than the distance d2 from theside wall 644 of theannular groove 640 to the recessedgroove 643. The width d3 of theprojection 661 of thepin 660 is smaller than the width d4 of the recessedgroove 643 of theannular groove 640. - Operation of the present embodiment will now be described.
- As illustrated in
FIG. 9 , when the driven-side rotational body 610 is in a state coupled to the drive-siderotational body 110, theactuator 150 is operated to insert thepin 660 of the lockingmember 650 into a startingend 632 of thehelical groove 630 of thegroove 620. This engages thepin 660 with aside wall 631 of thehelical groove 630 to lock the driven-siderotational body 120 against the urging force of the urgingmembers 135. Then, as the driven-side rotational body 610 is rotated, thepin 660 is moved relatively in thegroove 620 in a circumferential direction while being engaged with theside wall 631 of thehelical groove 630. Thepin 660 thus reaches theannular groove 640 and the driven-side rotational body 610 is moved to a decoupled position and rotated by inertial force. As a result, with reference toFIG. 8 , thepin 660 is switched to a state moving relatively in theannular groove 640. - As has been described, the length d1 from the side surface of the
pin 660 of the lockingmember 650 to theprojection 661 is substantially equal to but slightly greater than the distance d2 from theside wall 644 of theannular groove 640 to the recessedgroove 643. The width d3 of theprojection 661 of thepin 660 is smaller than the width d4 of the recessedgroove 643 of theannular groove 640. Therefore, when the driven-side rotational body 610 is rotated and thepin 660 is moved relatively in theannular groove 640, theprojection 661 of thepin 660 proceeds into the recessedgroove 643, which is formed in theannular groove 640, and becomes engaged with the recessedgroove 643. The recessedgroove 643 extends in the extending direction of theannular groove 640 and is formed over the entire length of theannular groove 640. As a result, even if the driven-side rotational body 610 is rotated by inertial force and thepin 660 is moved to the connectingportion 641 of theannular groove 640 such that thepin 660 and the side surface of thegroove 620, which is theside wall 644 of theannular groove 640 corresponding to thenon-connecting portion 642, become separate from each other, theprojection 661 of thepin 660 is engaged with the recessedgroove 643. Thepin 660 is thus maintained in theannular groove 640. - To switch the clutch 600 from the disengaged state to the engaged state, the
actuator 150 is operated to retract thepin 660 of the lockingmember 650 from theannular groove 640 of thegroove 620. This also causes retraction of theprojection 661 of thepin 660 from the recessedgroove 643 of theannular groove 640, thus disengaging theprojection 661 of thepin 660 and the recessedgroove 643 of theannular groove 640 from each other. The driven-siderotational body 510 is then moved to the coupled position by the urging force of the urgingmembers 135. As a result, the driven-siderotational body 510 and the drive-siderotational body 110 become coupled to each other, thus switching the clutch 500 to the engaged state. - The third embodiment achieves the following advantage (5) as well as an advantage equivalent to the advantage (1) of the first embodiment.
- (5) In the third embodiment, shifting of the
pin 660 from theannular groove 640 to thehelical groove 630 is restricted unless thepin 660 is shifted to be retracted from theannular groove 640 and the recessedgroove 643 and theprojection 661 of thepin 660 are disengaged from each other. That is, when thepin 660 is inserted in theannular groove 640, the recessedgroove 643 and theprojection 661 of thepin 660 function as a restricting portion. As a result, since shifting of thepin 660 from theannular groove 640 to thehelical groove 630 is restricted, it is possible to restrain shifting of the driven-side rotational body 610 to the coupled position despite the fact that thepin 660 is maintained in the recessedgroove 643. - As illustrated in
FIG. 11 , the present modification is different from the third embodiment in terms of the configuration of ahelical groove 680 of agroove 670 of the driven-side rotational body. Specifically, in the modification, a recessedgroove 681, which extends in the extending direction of thehelical groove 680, is formed also in thehelical groove 680. The recessedgroove 681 of thehelical groove 680 is connected to the recessedgroove 643 of theannular groove 640. - If the
actuator 150 is operated to insert thepin 660 of the lockingmember 650 into thehelical groove 630 of thegroove 620 when the driven-side rotational body 610 is in a state coupled to the drive-siderotational body 110, thepin 660 becomes engaged with theside wall 631 of thehelical groove 630. Also, theprojection 661 of thepin 660 proceeds into the recessedgroove 681 of thehelical groove 680 and becomes engaged with the recessedgroove 681. Then, when the driven-side rotational body is rotated and thepin 660 is moved relatively in thehelical groove 630, engagement between theprojection 661 and the recessedgroove 681 is maintained. In this state, where such engagement is maintained, thepin 660 reaches theannular groove 640. Therefore, after the pin reaches theannular groove 640, theprojection 661 proceeds into the recessedgroove 643 of theannular groove 640 through the connecting portion between the recessedgroove 681 of thehelical groove 680 and the recessedgroove 643 of theannular groove 640. That is, the recessedgroove 681 of thehelical groove 680 guides theprojection 661 of thepin 660 into the recessedgroove 643 of theannular groove 640. - Also in this embodiment, the recessed
groove 643 extends in the extending direction of theannular groove 640 and is formed over the entire length of theannular groove 640. As a result, even if the driven-side rotational body 610 is rotated by inertial force and thepin 660 is moved to the connectingportion 641 of theannular groove 640 such that thepin 660 and the side surface of thegroove 620 become separate from each other, theprojection 661 of thepin 660 is engaged with the recessedgroove 643. Thepin 660 is thus maintained in theannular groove 640. - The remainder of the configuration, the operation, and the advantages of the present modification are the same as those of the third embodiment.
- A clutch according to a fourth embodiment will now be described with reference to
FIG. 12 . - As illustrated in
FIG. 12 , a clutch 700 of the fourth embodiment is different from the illustrated embodiments in terms of the configuration of a driven-siderotational body 710 and the configuration of a lockingmember 750. The remainder of the configuration is the same as those of the first embodiment. Thus, like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted. Position change of eachball 130 in the correspondingball accommodating groove 127 caused by axial shifting of the driven-siderotational body 710 and switching between the engaged state and the disengaged state caused by such position change happen in the same manners as the first embodiment. Accordingly, illustration of theballs 130 and theball accommodating grooves 127 are omitted inFIG. 12 . - As illustrated in
FIG. 12 , agroove 720 of asmall diameter portion 711 of the driven-siderotational body 710 includes ahelical groove 730 inclined with respect to the axial direction and anannular groove 740, which is formed continuously from thehelical groove 730 and extends over the entire circumference of an outer circumferential surface of the driven-siderotational body 710 and perpendicularly to the axial direction. Theannular groove 740 of thegroove 720 has a depth equal to the depth of thehelical groove 730. InFIG. 12 , the boundary between a connecting portion of theannular groove 740, which is connected directly to thehelical groove 730, and thehelical groove 730 is represented by the long dashed double-short dashed line. - A
flange 770 projects from the outer circumferential surface of the driven-siderotational body 710 and extends over the entire circumference of the outer circumferential surface of the driven-siderotational body 710. Specifically, theflange 770 is arranged on an outer circumferential surface of thesmall diameter portion 711 of the driven-siderotational body 710. That is, theflange 770 is formed at a right side as viewed inFIG. 12A with respect to agroove 720 in the outer circumferential surface of the driven-side rotational body. Theflange 770 extends perpendicular to the axial direction of the driven-siderotational body 710 and parallel to theannular groove 740. - The locking
member 750 includes apin 760, which is inserted into thegroove 720 of the driven-siderotational body 710, and a one-way locking portion 780, which selectively proceeds and retreats with respect to the driven-siderotational body 710 as thepin 760 is inserted into or retracted from thegroove 720. In the fourth embodiment, the one-way locking portion 780 and theflange 770 of the driven-siderotational body 710 configure a restricting portion. - The one-
way locking portion 780 includes anengagement member 781 and anelastic member 785, which urges theengagement member 781 toward the driven-siderotational body 710. Theelastic member 785 is configured by, for example, a coil spring. The one-way locking portion 780 is located at the same side with respect to thepin 760 as the side at which theflange 770 is arranged with respect to the groove 720 (the right side as viewed inFIG. 12A ). - The right surface of the
flange 770 as viewed inFIG. 12A is referred to as afirst surface 771 and the left surface of theflange 770 as viewed in the drawing is referred to as asecond surface 772. The right surface of theengagement member 781 as viewed inFIG. 12A is referred to as afirst surface 782 and the left surface of theengagement member 781 as viewed in the drawing is referred to as asecond surface 783. The right surface of thepin 760 as viewed inFIG. 12A is referred to as afirst surface 761. In this case, the distances between the respective surfaces and the shapes of thesurfaces engagement member 781 are defined as follows. - As illustrated in
FIG. 12A , in the lockingmember 750, the distance d1 from thefirst surface 761 of thepin 760 to thesecond surface 783 of theengagement member 781 is substantially equal to but slightly greater than the distance d2 from aside wall 732 at a startingend 731 of thehelical groove 730 to thefirst surface 771 of theflange 770. The distance d3 from thefirst surface 761 of thepin 760 of the lockingmember 750 to thefirst surface 782 of theengagement member 781 is substantially equal to but slightly smaller than the distance d4 from aside wall 741 of the annular groove 740 (the position represented by the long dashed double-short dashed line in the connecting portion of the annular groove 740) to thesecond surface 772 of theflange 770. In theengagement member 781, the distal end of thefirst surface 782 is a corner and the distal end of thesecond surface 783 is a chamfered round surface. That is, thesecond surface 783 is inclined such that thefirst surface 782 approaches thefirst surface 782 in a distal direction. In other words, the distal end of theengagement member 781 is inclined and becomes gradually smaller in size. - Accordingly, when the driven-side
rotational body 710 is in a coupled state and thepin 760 is inserted in the startingend 731 of thehelical groove 730 of thegroove 720 as illustrated inFIG. 12B , thesecond surface 783 of theengagement member 781 is in contact with thefirst surface 771 of theflange 770. Thesecond surface 783 of theengagement member 781, which contacts theflange 770 at this stage, has the inclined distal end as has been described. Also, referring toFIG. 12D , when thepin 760 is inserted in theannular groove 740 of thegroove 720, theengagement member 781 is in contact with thesecond surface 772 of theflange 770. The distal end of thefirst surface 782 of theengagement member 781, which contacts theflange 770 at this stage, is the corner as has been described. - Operation of the present embodiment will now be described.
- Referring to
FIG. 12A , the driven-siderotational body 710 is located at a coupled position and the driven-siderotational body 710 is in a state coupled to the drive-siderotational body 110. In this state, by operating theactuator 150 to insert thepin 760 of the lockingmember 750 into thehelical groove 730 of thegroove 720, the state illustrated in.FIG. 12B is brought about. In this manner, thepin 760 is engaged with aside wall 732 of thehelical groove 730, thus locking the driven-siderotational body 120 against the urging force of the urgingmembers 135. Then, as the driven-siderotational body 710 is rotated, thepin 760 is moved relatively in thegroove 720 in a circumferential direction while being engaged with theside wall 732 of thehelical groove 730. The driven-siderotational body 710 is thus shifted from the coupled position to a decoupled position. - As the driven-side
rotational body 710 is shifted to the decoupled position, the position of thepin 760 in thegroove 720 is shifted relatively in a direction from thehelical groove 730 toward theannular groove 740. Correspondingly, theengagement member 781, which is fixed to the lockingmember 750 together with thepin 760, is shifted relative to the driven-siderotational body 710. As illustrated inFIG. 123 , when thepin 760 is inserted in the startingend 731 of thehelical groove 730 of thegroove 720, theengagement member 781 faces thefirst surface 771 of theflange 770. Thesecond surface 783 of theengagement member 781, which faces theflange 770, has the inclined distal end. That is, the surface by which theengagement member 781 contacts theflange 770 when the driven-siderotational body 710 is shifted from the coupled position to the decoupled position is inclined. Therefore, when the driven-siderotational body 710 is moved from the coupled position to the decoupled position, theflange 770 and theengagement member 781 contact each other, as illustrated inFIG. 12C , to cause the force for pressing theengagement member 781 back against the urging force of theelastic member 785 such that theengagement member 781 moves past theflange 770. In this manner, when thepin 760 is inserted in thehelical groove 730 of thegroove 720, movement of the driven-siderotational body 710 from the coupled position to the decoupled position is permitted despite the fact that theengagement member 781 is in contact with theflange 770. - Then, as illustrated in
FIG. 12D , when the driven-siderotational body 710 is rotated by inertial force at the decoupled position and thepin 760 is moved relatively in theannular groove 740, theengagement member 781 faces thefirst surface 771 of theflange 770. As has been described, thefirst surface 782 of theengagement member 781 contacts theflange 770 in this state and the distal end of thefirst surface 782 is the corner. Therefore, when thepin 760 is moved relatively in theannular groove 740 of thegroove 720, theengagement member 781 is prevented from being pressed back by theflange 770 against the urging force of theelastic member 785, and engagement between theengagement member 781 and theflange 770 is thus maintained. In this manner, movement of the driven-siderotational body 710 from the decoupled position to the coupled position is restricted. That is, even when the driven-siderotational body 710 is arranged at the decoupled position and rotated by inertial force and, in this state, thepin 760 is moved to the connecting portion of theannular groove 740 to separate thepin 760 from the side surface of the groove 720 (theside wall 741 of the annular groove 740), the one-way locking portion 780 restricts shifting of the driven-siderotational body 710. Thepin 760 is thus held in theannular groove 740. - To switch the clutch 700 from the disengaged state to the engaged state, the
actuator 150 is operated to retract thepin 760 of the lockingmember 750 from theannular groove 740 of thegroove 720. This also causes disengagement between theengagement member 781 and theflange 770. The driven-siderotational body 710 is thus moved to the coupled position by the urging force of the urgingmembers 135. As a result, the driven-siderotational body 710 and the drive-siderotational body 110 become coupled to each other, thus switching the clutch 700 to the engaged state. - The fourth embodiment achieves the following advantage (6) as well as an advantage equivalent to the advantage (1) of the first embodiment.
- (6) Unless the
pin 760 is shifted to be retracted from theannular groove 740 to disengage theflange 770 and the one-way locking portion 780 from each other, thepin 760 is not shifted from theannular groove 740 to thehelical groove 730. That is, theflange 770 and the one-way locking portion 780 function as a restricting portion. This restricts shifting of thepin 760 from theannular groove 740 to thehelical groove 730 when thepin 760 is inserted in theannular groove 740. As a result, it is possible to restrain shifting of the driven-siderotational body 710 to the coupled position despite the fact that thepin 760 is maintained in thegroove 720. - A clutch according to a fifth embodiment will now be described.
- As illustrated in
FIG. 13 , a clutch 800 of the fifth embodiment is different from the fourth embodiment in terms of the configuration of the lockingmember 750. The remainder of the configuration is the same as those of the first embodiment. Thus, like or the same reference numerals are given to those components that are like or the same as the corresponding components of the first embodiment and detailed explanations are omitted. The fifth embodiment is the same as the first embodiment in terms of position change of eachball 130 in the correspondingball accommodating groove 127 caused by axial shifting of the driven-siderotational body 710 and switching between the engaged state and the disengaged state caused by such position change. Accordingly, illustration of theballs 130 and theball accommodating grooves 127 is omitted also inFIG. 13 . - With reference to
FIG. 13 , the driven-siderotational body 710 of the fifth embodiment is configured identically with the driven-siderotational body 710 of the fourth embodiment. Theflange 770 is formed in the driven-siderotational body 710. - A locking
member 850 includes apin 860, which is inserted into thegroove 720 of the driven-siderotational body 710, and a one-way locking portion 880, which selectively proceeds and retreats with respect to the driven-siderotational body 710 as thepin 860 is inserted into or retracted from thegroove 720. In the fifth embodiment, the one-way locking portion 880 and theflange 770 of the driven-siderotational body 710 configure a restricting portion. - The one-
way locking portion 880 includes anengagement member 881, apivot shaft 885 through which theengagement member 881 is pivotally supported by the lockingmember 850, and a restrictingmember 888, which restricts pivot of theengagement member 881 in a certain direction (a leftward direction inFIG. 13A ). As illustrated inFIG. 13A , a state in which the distal end of theengagement member 881 projects toward the driven-siderotational body 710 is defined as a reference position of theengagement member 881. The restrictingmember 888 restricts tilting of theengagement member 881 in a specific direction from the reference position and permits tilting of theengagement member 881 in another direction (a rightward direction inFIG. 13A ) from the reference position. - The right surface of the
flange 770 as viewed inFIG. 13A is referred to as thefirst surface 771 and the left surface of theflange 770 as viewed in the drawing is referred to as thesecond surface 772. The right surface of theengagement member 881 as viewed inFIG. 13A and the left surface of theengagement member 881 as viewed in the drawing when theengagement member 881 is arranged at the reference position are referred to as afirst surface 882 and asecond surface 883, respectively. The right surface of thepin 860 as viewed inFIG. 13A is referred to as afirst surface 861. - In this case, the distances between the respective surfaces are defined as follows.
- As illustrated in
FIG. 13A , in the lockingmember 850, the distance d1 from thefirst surface 861 of thepin 860 to thesecond surface 883 of theengagement member 881 is substantially equal to but slightly greater than the distance d2 from theside wall 732 of thehelical groove 730 at the startingend 731 to thefirst surface 771 of theflange 770. The distance d3 from thefirst surface 861 of thepin 860 of the lockingmember 850 to thefirst surface 882 of theengagement member 881 is substantially equal to but slightly smaller than the length d4 from theside wall 741 of the annular groove 740 (the position represented by the long dashed double-short dashed line corresponding to the boundary position between theannular groove 740 and thehelical groove 730 in the connecting portion of the annular groove 740) to thesecond surface 772 of theflange 770. - Accordingly, when the driven-side
rotational body 710 is in a coupled state and thepin 860 is inserted in the startingend 731 of thehelical groove 730 of thegroove 720 as illustrated inFIG. 13B , thesecond surface 883 of theengagement member 881 is in contact with thefirst surface 771 of theflange 770. Also, as illustrated inFIG. 13D , when thepin 860 is arranged in theannular groove 740 of thegroove 720, theengagement member 881 is in contact with thesecond surface 772 of theflange 770. - Operation of the present embodiment will now be described.
- Referring to
FIG. 13A , the driven-siderotational body 710 is located at a coupled position and the driven-siderotational body 710 is in a state coupled to the drive-siderotational body 110. In this state, by operating theactuator 150 to insert thepin 860 of the lockingmember 850 into the startingend 731 of thehelical groove 730 of thegroove 720, the state illustrated inFIG. 13B is brought about. In this manner, thepin 860 is engaged with theside wall 732 of thehelical groove 730, thus locking the driven-siderotational body 120 against the urging force of the urgingmembers 135. Then, as the driven-siderotational body 710 is rotated, thepin 860 is moved relatively in thegroove 720 in a circumferential direction while being engaged with theside wall 732 of thehelical groove 730. The driven-siderotational body 710 is thus shifted from the coupled position to a decoupled position. - As the driven-side
rotational body 710 is shifted to the decoupled position, the position of thepin 860 in thegroove 720 is shifted relatively in a direction from thehelical groove 730 toward theannular groove 740. Correspondingly, theengagement member 881, which is fixed to the lockingmember 850 together with thepin 860, is shifted relative to the driven-siderotational body 710. As illustrated inFIG. 13B , when thepin 860 is inserted in the startingend 731 of thehelical groove 730, theengagement member 881 is in contact with thefirst surface 771 of theflange 770. Theengagement member 881 is permitted to tilt in the certain direction (the rightward direction as viewed inFIGS. 13 ) from the reference position, at which theengagement member 881 contacts theflange 770. Therefore, when the driven-siderotational body 710 is moved from the coupled position to the decoupled position, theengagement member 881 contacts theflange 770 and tilts, thus moves past theflange 770, as illustrated inFIG. 13C . In this manner, when thepin 860 is inserted in the startingend 731 of thehelical groove 730, movement of the driven-siderotational body 710 from the coupled position to the decoupled position is permitted despite the fact that theengagement member 881 is in contact with theflange 770. - Then, as illustrated in
FIG. 13D , when the driven-siderotational body 710 is rotated by inertial force at the decoupled position and thepin 860 is moved relatively in theannular groove 740, theengagement member 881 faces thesecond surface 772 of theflange 770 and thefirst surface 882 of theengagement member 881 contacts and becomes engaged with thesecond surface 772 of theflange 770. When thepin 860 is moved relatively in theannular groove 740 of thegroove 720, tilting of theengagement member 881 in the certain direction (the leftward direction as viewed inFIG. 13D ) is restricted by the restrictingmember 888. Theengagement member 881 is thus prevented from tilting even if the urging force of the urgingmembers 135 acts on the driven-siderotational body 710 such that theengagement member 881 is pressed by theflange 770. As a result, theengagement member 881 is held at the reference position, thus maintaining engagement between theengagement member 881 and theflange 770. This restricts movement of the driven-siderotational body 710 from the decoupled position to the coupled position. That is, even when the driven-siderotational body 710 is arranged at the decoupled position and rotated by inertial force and, in this state, thepin 860 is moved to the connecting portion of theannular groove 740 such that thepin 860 becomes separate from the side surface of the groove 720 (theside wall 741 of the annular groove 740), the one-way locking portion 880 restricts shifting of the driven-siderotational body 710. Thepin 860 is thus held in theannular groove 740. - To switch the clutch 800 from the disengaged state to the engaged state, the
actuator 150 is operated to retract thepin 860 of the lockingmember 850 from theannular groove 740 of thegroove 720. This also causes disengagement between theengagement member 881 and theflange 770. The driven-siderotational body 710 is thus moved to the coupled position by the urging force of the urgingmembers 135. As a result, the driven-siderotational body 710 and the drive-siderotational body 110 become coupled to each other, thus switching the clutch 800 to the engaged state. - The fifth embodiment achieves advantages equivalent to the advantage (1) of the first embodiment and the advantage (6) of the fourth embodiment.
- The clutch according to the present disclosure is not restricted to the configurations illustrated in the above-described embodiments but may be embodied in, for example, the forms described below, which are modifications of the embodiments.
- In the first embodiment, the depth of the
annular groove 420 is small in the vicinity of the startingend 421 relative to the depths of the other portions in the circumferential direction of the driven-siderotational body 120. The depth of thehelical groove 410 becomes gradually greater from the startingend 411 to the finishingend 412. However, the depth of the annular groove or the depth of the helical groove may be uniform in the circumferential direction. That is, the step between the annular groove and the helical groove may be set to a uniform size in the circumferential direction of the driven-siderotational body 120. - In the second embodiment, the protrusion is formed over the entire length of the connecting portion of the groove. The opposite ends of the protrusion reach the non-connecting portion. However, if the protrusion is formed at least over the entire length of the connecting portion of the groove, shifting of the pin into the helical groove can be restrained by engaging the protrusion with the recess of the pin over the entire length of the connecting portion. The opposite ends of the protrusion thus do not necessarily have to reach the non-connecting portion. For example, only one of the end portions may reach the non-connecting portion. Alternatively, the length of the protrusion may be equal to the length of the connecting portion such that neither end portion reaches the non-connecting portion. Further, as long as shifting of the pin from the annular groove into the helical groove is restrained and disengagement of the clutch is restrained, the protrusion does not necessarily have to extend over the entire length of the connecting portion. For example, the protrusion may be provided in a portion of the connecting portion of the groove.
- In the third embodiment and its modification, the recessed groove is formed over the entire length of the annular groove. However, the recessed groove only has to be formed at least over the entire length of the connecting portion of the annular groove. That is, if the protrusion is formed at least over the entire length of the connecting portion, shifting from the annular groove into the helical groove is restrained. Further, if shifting of the pin from the annular groove into the helical groove is restrained and disengagement of the clutch is restrained, the recessed groove may be formed in a portion of the connecting portion.
- In the fourth and fifth embodiments, the flange is formed over the entire circumference of the outer circumferential surface of the driven-side rotational body. However, if shifting of the pin from the annular groove into the helical groove is restrained and disengagement of the clutch is restrained, the flange does not necessarily have to extend over the entire circumference but may be arranged in a portion of the outer circumferential surface to extend in the circumferential direction of the driven-side rotational body.
- The number of the urging members may be modified as needed. For example, a single urging member may be employed to urge the driven-side rotational body.
- Any suitable urging member may be employed as long as the urging member urges the driven-side rotational body toward the coupled position. The urging member is thus not restricted to the aforementioned compression coil spring. For example, a tension spring for pulling the driven-side rotational body toward the coupled position may be employed as the urging member.
- The actuator is not restricted to the self-holding type solenoid but may be, for example, a solenoid having a locking member that is inserted into a groove only when a coil is energized. In this configuration, the clutch is disengaged only when the coil is energized. The clutch is thus maintained in the engaged state if the coil cannot be energized. As a result, even when the actuator fails to operate normally, the pump can be operated.
- The actuator is not restricted to a solenoid. That is, any other suitable actuator than the solenoid, such as a hydraulic type actuator, may be used to selectively insert and retract the locking member. Also in this case, the clutch is disengaged through engagement between a groove of the driven-side rotational body and the locking member. The force needed to disengage the clutch is thus obtained from rotational force of the driven-side rotational body. As a result, disengagement is carried out by small force.
- The clutch is not restricted to the configuration in which drive force is transmitted through the balls. The clutch may be a pressing type clutch.
- For example, opposed surfaces of the driven-side rotational body and the drive-side rotational body may be parallel tapered surfaces each inclined with respect to the axial direction. The tapered surfaces serve as pressing surfaces. By moving the driven-side rotational body in the axial direction and pressing the pressing surfaces against each other, the driven-side rotational body and the drive-side rotational body are coupled to each other.
- In the clutch of each of the illustrated embodiments, the shapes of the components are not restricted particularly to the shapes of the illustrated embodiments, as long as the operation illustrated for each embodiment is ensured. For example, as illustrated in
FIG. 14 ,ball accommodating grooves 927 may be formed in alarge diameter portion 922 of a driven-siderotational body 910 and recesses 928 may be formed by lightening portions that lack theball accommodating grooves 927. This decreases the weight of the driven-siderotational body 910 and thus reduces the inertial force caused by the driven-siderotational body 910. As a result, when the driven-siderotational body 910 reaches a decoupled position, rotation of the driven-siderotational body 910 quickly stops. - In each of the illustrated embodiments, the clutch switches the state of power transmission from the crankshaft to the pump. However, the clutch according to the present disclosure may be employed as a clutch arranged between other auxiliary devices, such as a compressor or an oil pump, and the crankshaft. Also, the clutch according to the present disclosure is not restricted to the clutch for switching the state of power transmission from the crankshaft but may be used as a clutch for switching the state of power transmission from other drive sources.
Claims (4)
1. A clutch comprising:
a drive-side rotational body;
a driven-side rotational body movable in an axial direction of the drive-side rotational body between a coupled position at which the driven-side rotational body is coupled to the drive-side rotational body and a decoupled position at which the driven-side rotational body is decoupled from the drive-side rotational body;
an urging member that urges the driven-side rotational body from the decoupled position toward the coupled position;
a groove formed in an outer circumferential surface of the driven-side rotational body, wherein the groove has a helical portion that extends about an axis of the driven-side rotational body and an annular portion that is formed continuously from the helical portion and extends over an entire circumference of the driven-side rotational body and perpendicularly to the axial direction;
a pin that is selectively inserted into and retracted from the groove and restricted from moving in the axial direction, wherein, when the pin is in a state inserted in the helical portion and engaged with a side wall of the helical portion, the position of the pin is shifted from the helical portion to the annular portion through rotation of the driven-side rotational body such that the driven-side rotational body is moved to the decoupled position against urging force of the urging member; and
a restricting portion that restricts shifting of the position of the pin from the annular portion to the helical portion when the pin is in a state located in the annular portion.
2. The clutch according to claim 1 , wherein
the helical portion is a helical groove,
the annular portion is an annular groove having a depth greater than the depth of the helical groove,
the groove includes a step in a connecting portion by which the helical groove and the annular groove are connected to each other, and
a side wall of the step functions as the restricting portion.
3. The clutch according to claim 1 , wherein
the helical portion is a helical groove,
the annular portion is an annular groove including a connecting portion connected to the helical groove, and
the restricting portion includes a protrusion and a recess, wherein the protrusion projects from a bottom surface of the annular groove and extends at least over an entire length of the connecting portion in the extending direction of the annular groove, and the recess is formed at a distal end of the pin and becomes engaged with the protrusion when the pin is arranged in the connecting portion.
4. The clutch according to claim 1 , wherein
the helical portion is a helical groove,
the annular portion is an annular groove including a connecting portion connected to the helical groove, and
the restricting portion includes a recessed groove and a projection, wherein the recessed groove is formed in a bottom surface of the annular groove and extends at least over an entire length of the connecting portion in the extending direction of the annular groove, and the projection projects from a distal end of the pin and becomes engaged with the recessed groove when the pin is arranged in the connecting portion.
Applications Claiming Priority (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2012-211046 | 2012-09-25 | ||
JP2012211046A JP5724978B2 (en) | 2012-09-25 | 2012-09-25 | clutch |
JP2013154986A JP5796609B2 (en) | 2013-07-25 | 2013-07-25 | clutch |
JP2013-154986 | 2013-07-25 | ||
JP2013-194686 | 2013-09-19 | ||
JP2013194686A JP5880507B2 (en) | 2013-09-19 | 2013-09-19 | clutch |
PCT/JP2013/075874 WO2014050869A1 (en) | 2012-09-25 | 2013-09-25 | Clutch |
Publications (1)
Publication Number | Publication Date |
---|---|
US20150247536A1 true US20150247536A1 (en) | 2015-09-03 |
Family
ID=50388265
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/428,853 Abandoned US20150247536A1 (en) | 2012-09-25 | 2013-09-25 | Clutch |
US14/428,550 Expired - Fee Related US9759272B2 (en) | 2012-09-25 | 2013-09-25 | Clutch having a groove formed in an outer circumferential surface |
US14/429,666 Abandoned US20150252857A1 (en) | 2012-09-25 | 2013-09-25 | Clutch |
Family Applications After (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/428,550 Expired - Fee Related US9759272B2 (en) | 2012-09-25 | 2013-09-25 | Clutch having a groove formed in an outer circumferential surface |
US14/429,666 Abandoned US20150252857A1 (en) | 2012-09-25 | 2013-09-25 | Clutch |
Country Status (4)
Country | Link |
---|---|
US (3) | US20150247536A1 (en) |
CN (3) | CN104662322A (en) |
DE (3) | DE112013004676T5 (en) |
WO (3) | WO2014050870A1 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150247535A1 (en) * | 2012-09-25 | 2015-09-03 | Toyota Jidosha Kabushiki Kaisha | Clutch |
US11655861B2 (en) | 2020-09-25 | 2023-05-23 | T.P.P. Co. | Friction clutch pressure plate device |
Families Citing this family (2)
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US10094427B2 (en) * | 2015-10-20 | 2018-10-09 | GM Global Technology Operations LLC | Ball cam actuated dog clutch |
CN112377513B (en) * | 2020-11-03 | 2021-10-01 | 山东正工机械有限公司 | Transmission shaft structure capable of being assembled in multi-section split mode |
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- 2013-09-25 WO PCT/JP2013/075875 patent/WO2014050870A1/en active Application Filing
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- 2013-09-25 CN CN201380049362.3A patent/CN104662321B/en not_active Expired - Fee Related
- 2013-09-25 WO PCT/JP2013/075874 patent/WO2014050869A1/en active Application Filing
- 2013-09-25 US US14/429,666 patent/US20150252857A1/en not_active Abandoned
- 2013-09-25 CN CN201380049415.1A patent/CN104685254A/en active Pending
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Also Published As
Publication number | Publication date |
---|---|
CN104662322A (en) | 2015-05-27 |
DE112013004673T5 (en) | 2015-07-09 |
DE112013004676T5 (en) | 2015-08-06 |
CN104662321A (en) | 2015-05-27 |
US9759272B2 (en) | 2017-09-12 |
DE112013004677T5 (en) | 2015-07-16 |
WO2014050869A1 (en) | 2014-04-03 |
CN104662321B (en) | 2017-03-15 |
US20150247535A1 (en) | 2015-09-03 |
US20150252857A1 (en) | 2015-09-10 |
WO2014050868A1 (en) | 2014-04-03 |
WO2014050870A1 (en) | 2014-04-03 |
DE112013004677B4 (en) | 2021-11-18 |
CN104685254A (en) | 2015-06-03 |
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Legal Events
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AS | Assignment |
Owner name: TOYOTA JIDOSHA KABUSHIKI KAISHA, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SUNADA, HIROTAKA;NAKAYAMA, MASAO;TSUTSUI, HIDEKI;AND OTHERS;SIGNING DATES FROM 20150216 TO 20150223;REEL/FRAME:035184/0089 |
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STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |