JP5208809B2 - Automatic transmission - Google Patents

Description

  The present invention relates to an automatic transmission that shifts the rotation of an input member to a plurality of stages and transmits it to an output member.

  2. Description of the Related Art Conventionally, there is known an automatic transmission that shifts the rotation of an input member to a plurality of stages through a plurality of planetary gears arranged in a transmission case and transmits it to an output member.

  For example, Patent Documents 1 and 2 describe an automatic transmission that includes three sets of planetary gears, four clutches and two brakes as engagement elements, and ensures eight forward speeds. At each shift stage, two engaging elements are engaged and four engaging elements are released.

JP 2003-130152 A JP 2005-273768 A

  In the automatic transmissions described in Patent Documents 1 and 2, the engagement elements are four clutches and two brakes, and the number of clutches is larger than that of the brakes. Unlike the brake piston provided on the transmission case, the clutch piston is provided on the input shaft that is the input member, the main shaft that supports the input shaft, etc., and is disposed radially outward of the planetary gear. I can't. For this reason, when the number of clutches is large, there is a problem that the shaft length of the automatic transmission and thus the total length becomes long.

  In addition, two engagement elements are engaged in each shift stage, and the number of open engagement elements is as large as four, resulting in a large friction loss due to dragging of the open engagement elements. For this reason, there exists a malfunction that the transmission efficiency of a transmission is inferior.

  In view of the above, it is an object of the present invention to provide an automatic transmission with a small number of clutches and a small number of engagement elements to be released.

In order to achieve the above object, a first aspect of the present invention comprises three elements, a sun gear, a carrier, and a ring gear, respectively, and the first member through the fourth planetary gear disposed in the transmission case are used for the input member. An automatic transmission that shifts rotation to a plurality of stages and transmits the output to an output member, wherein the three elements of the first planetary gear are arranged in the order corresponding to the gear ratio in the speed diagram in the order of the first element and the first element, respectively. 2 elements and 3 elements, 3 elements of the second planetary gear are respectively 4 elements, 5 elements and 6 elements, and 3 elements of the 3rd planetary gear are respectively 7 elements, 8 elements and 8 elements. 9 elements , 3 elements of the 4th planetary gear as 10th element, 11th element and 12th element respectively, the input member is connected to the 3rd element, and the 2nd element and 4th element are connected to 1 connected body is formed, and the fifth The element and the seventh element are connected to form a second connecting body, the sixth element, the eighth element, and the tenth element are connected to form a third connecting body, and the eleventh element is an output member. The first clutch that can be switched between a state in which the second connector and the twelfth element are connected to each other and a state in which the connection is cut off, and a state in which the ninth element and the twelfth element are connected to each other and the connection is cut off. A second clutch that can be switched to a state, a third clutch that can be switched between a state in which the input member and the twelfth element are connected, and a state in which the connection is cut off, and a state in which the first coupling body is fixed to the transmission case A first brake that can be switched to a state of releasing the fixing, a second brake that can be switched to a state of fixing the second connecting body to the transmission case, and a state of releasing the fixing, and a first element. Switch between the state of fixing to the transmission case and the state of releasing this fixing. Characterized in that it comprises a a third brake.

  According to the first aspect of the present invention, as is apparent from the description of the embodiment described later, it is possible to ensure a forward eight-speed shift with three clutches and three brakes. Therefore, the overall length of the automatic transmission can be shortened as compared with the automatic transmissions described in Patent Documents 1 and 2 above.

  In each shift stage, the number of engagement elements to be released is all three, and the number of engagement elements to be released is one compared to the automatic transmissions described in Patent Documents 1 and 2 above. Can be reduced. Therefore, friction loss due to drag is reduced, and transmission efficiency of the automatic transmission can be improved.

The second aspect of the present invention comprises three elements, a sun gear, a carrier, and a ring gear, respectively, and the rotation of the input member is shifted in a plurality of stages via first to fourth planetary gears arranged in the transmission case. In which the three elements of the first planetary gear are defined as a first element, a second element, and a third element, respectively, in the order of arrangement at intervals corresponding to the gear ratio in the speed diagram. The three elements of the second planetary gear are the fourth element, the fifth element, and the sixth element, respectively, and the three elements of the third planetary gear are the seventh element, the eighth element, and the ninth element, respectively, three elements respectively first 10 elements, as the 11 elements and 12 elements, the input member is connected to the third element, the first connection body and connects the second element and the fourth element is constituted, Connecting the fifth and seventh elements The second connector is configured, and the sixth component, the eighth component, and the tenth component are connected to form the third connector, and the eleventh component is connected to the output member. A first clutch that can be switched between a state in which the 12 elements are connected and a state in which the connection is disconnected; a second clutch that is switchable between a state in which the ninth element and the eleventh element are connected and a state in which the connection is disconnected; A third clutch that can be switched between a state in which the input member and the twelfth element are connected and a state in which the connection is cut off, and a state in which the first connecting body is fixed to the transmission case and a state in which the fixing is released. A first brake that can be freely switched, a second brake that can be switched between a state in which the second coupling body is fixed to the transmission case and a state in which the fixing is released, a state in which the first element is fixed to the transmission case, and this fixing A third brake that can be switched to a state of releasing It is characterized in.

  According to the second aspect of the present invention, as will be apparent from the description of the embodiment described later, it is possible to secure a forward eight-speed shift with three clutches and three brakes. Therefore, the overall length of the automatic transmission can be shortened as compared with the automatic transmissions described in Patent Documents 1 and 2 above.

  In each shift stage, the number of engagement elements to be released is all three, and the number of engagement elements to be released is one compared to the automatic transmissions described in Patent Documents 1 and 2 above. Can be reduced. Therefore, friction loss due to drag is reduced, and transmission efficiency of the automatic transmission can be improved.

  Further, in the first and second aspects of the present invention, the fifth element of the second planetary gear and the seventh element of the third planetary gear are integrated, and the sixth element of the second planetary gear and the eighth element of the third planetary gear. If the elements are integrated and the second planetary gear and the third planetary gear constitute a Ravigneaux type double planetary gear, all the axes of the automatic transmission can be made shorter.

  Further, in the first and second aspects of the present invention, if the third clutch is constituted by a dog clutch or a synchro clutch, the structure can be simplified as compared with the third clutch constituted by a multi-plate clutch. Therefore, all the axes of the automatic transmission can be made shorter.

(A) is a skeleton diagram of the first embodiment of the automatic transmission according to the present invention, and (b) is a diagram collectively showing the relationship between each shift stage and the engagement state of each engagement element. The speed diagram of the 1st thru | or 4th planetary gear of 1st Embodiment. (A) is a skeleton figure of 2nd Embodiment of the automatic transmission which concerns on this invention, (b) is a figure which shows collectively the relationship between each gear stage and the engagement state of each engagement element. The speed diagram of the 1st thru | or 4th planetary gear of 2nd Embodiment. The skeleton figure of 3rd Embodiment of the automatic transmission which concerns on this invention. The skeleton figure of 4th Embodiment of the automatic transmission which concerns on this invention. The skeleton figure of 5th Embodiment of the automatic transmission which concerns on this invention.

[First Embodiment]
A first embodiment of an automatic transmission according to the present invention will be described with reference to FIGS. 1 and 2. The automatic transmission includes an input shaft 2 that is rotatably supported in a transmission case 1 and that is connected to a power source such as an engine (not shown), and an output member that is disposed concentrically with the input shaft 2. The output gear 3 is provided. The rotation of the output gear 3 is transmitted to the left and right drive wheels of the vehicle via a differential gear (not shown). This automatic transmission is mounted horizontally so that the input shaft 2 faces in the width direction of the vehicle, and therefore can be suitably mounted for an FF (front engine / front drive) vehicle having a large total length restriction.

  In the transmission case 1, a double planetary gear for shifting, which is positioned around the input shaft 2, is composed of a first planetary gear 4 for input, a second planetary gear 5, and a third planetary gear 6, and for output The fourth planetary gear 7 is arranged.

  The first planetary gear 4 is formed of a single pinion type planetary gear that includes a sun gear Sf, a ring gear Rf, and a carrier Cf that meshes with each other and supports the pinion Pf that meshes with the sun gear Sf and the ring gear Rf so as to rotate and revolve. ing.

  Referring to the velocity diagram of the first planetary gear 4 shown in the upper part of FIG. 2, three elements including the sun gear Sf, the carrier Cf, and the ring gear Rf of the first planetary gear 4 are separated by a distance corresponding to the gear ratio in the velocity diagram. If the first element, the second element, and the third element are arranged from the left side in the order in which they are arranged, the first element is the sun gear Sf, the second element is the carrier Cf, and the third element is the ring gear Rf. The ratio between the distance between the sun gear Sf and the carrier Cf and the distance between the carrier Cf and the ring gear Rf is set to i: 1 where i is the gear ratio of the first planetary gear 4 (number of teeth of the ring gear / number of teeth of the sun gear). Is set. The ring gear Rf is connected to the input shaft 2. In the velocity diagram, the lower horizontal line and the upper horizontal line indicate that the rotational speeds are “0” and “1” (the same rotational speed as the input shaft 2), respectively.

  The compound planetary gear is composed of a second planetary gear 5 and a third planetary gear 6. The second planetary gear 5 is composed of a single pinion type planetary gear including a sun gear Sm, a ring gear Rm, and a carrier Cm that supports a pinion Pm meshing with the sun gear Sm and the ring gear Rm so as to rotate and revolve. The third planetary gear 6 is also composed of a single pinion type planetary gear including a sun gear Sa, a ring gear Ra, and a carrier Ca that supports the pinion Pa meshing with the sun gear Sa and the ring gear Ra so as to rotate and revolve.

  Referring to the speed diagram of the double planetary gear shown in the middle of FIG. 2, the three elements including the sun gear Sm, the carrier Cm, and the ring gear Rm of the second planetary gear 5 are arranged at intervals corresponding to the gear ratio in the speed diagram. Assuming that the fourth element, the fifth element, and the sixth element are arranged in order from the left side, the fourth element is the sun gear Sm, the fifth element is the carrier Cm, and the sixth element is the ring gear Rm. The ratio between the distance between the sun gear Sm and the carrier Cm and the distance between the carrier Cm and the ring gear Rm is set to j: 1 where j is the gear ratio of the second planetary gear 5.

  Further, referring to the speed diagram of the above-mentioned planetary gear, the three elements including the sun gear Sa, the carrier Ca, and the ring gear Ra of the third planetary gear 6 are arranged in the order in the order corresponding to the gear ratio in the speed diagram. , The seventh element is the ring gear Ra, the eighth element is the carrier Ca, and the ninth element is the sun gear Sa. The ratio between the distance between the sun gear Sa and the carrier Ca and the distance between the carrier Ca and the ring gear Ra is set to k: 1 where k is the gear ratio of the third planetary gear 6.

  The fourth planetary gear 7 is composed of a single pinion type planetary gear comprising a sun gear Sr, a ring gear Rr, and a carrier Cr that supports the pinion Pr meshing with the sun gear Sr and the ring gear Rr so as to rotate and revolve.

  Referring to the velocity diagram of the fourth planetary gear 7 shown in the lower part of FIG. 2, the three elements including the sun gear Sr, the carrier Cr, and the ring gear Rr of the fourth planetary gear 7 are arranged at intervals corresponding to the gear ratio in the velocity diagram. If the tenth element, the eleventh element, and the twelfth element are arranged from left to right in the order of arrangement, the tenth element is the ring gear Rr, the eleventh element is the carrier Cr, and the twelfth element is the sun gear Sr. The ratio between the distance between the sun gear Sr and the carrier Cr and the distance between the carrier Cr and the ring gear Rr is set to m: 1 where m is the gear ratio of the fourth planetary gear 7.

  Here, the input shaft 2 is connected to the ring gear Rf (third element) of the first planetary gear 4, and the carrier Cf (second element) of the first planetary gear 4 and the sun gear Sm (fourth element) of the second planetary gear 5 are connected. The first connecting bodies Cf and Sm are connected to each other, and the carrier Cm (fifth element) of the second planetary gear 5 and the ring gear Ra (seventh element) of the third planetary gear 6 are connected to form the second connecting body Cm. , Ra, and a ring gear Rm (sixth element) of the second planetary gear 5, a carrier Ca (eighth element) of the third planetary gear 6, and a ring gear Rr (tenth element) of the fourth planetary gear 7 are connected to each other. Three linked bodies Rm, Ca, and Rr are configured, and the carrier Cr (11th element) of the fourth planetary gear 7 is coupled to the output gear 3.

  In addition, three multi-plate clutches C1 to C3 and three brakes B1 to B3 are provided as engaging elements. The first clutch C1 engages the second coupling body Cm, Ra and the sun gear Sr (the twelfth element) of the fourth planetary gear 7 so as to be switchable between a state where the first clutch C1 is disconnected and a state where the connection is broken. Is engaged in a switchable manner between a state in which the sun gear Sa (9th element) of the third planetary gear 6 and the sun gear Sr (12th element) of the fourth planetary gear 7 are connected and a state in which the connection is cut off. C3 engages in a switchable manner between a state in which the sun gear Sr (the twelfth element) of the fourth planetary gear 7 is connected to the input shaft 2 and a state in which the connection is broken.

  The first brake B1 engages in a switchable manner between a state in which the first connecting bodies Cf and Sm are fixed to the transmission case 1 and a state in which the fixing is released, and the second brake B2 is connected to the second connecting body. The third brake B3 engages the sun gear Sf (first element) of the first planetary gear 4 in a transmission case. 1 is engaged in a switchable manner between a state of fixing to 1 and a state of releasing the fixing.

  In the first embodiment configured as described above, when the third clutch C3, the second brake B2, and the third brake B3 are engaged, the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 rotate. The speed is “1”, the rotational speed of the sun gear Sf of the first planetary gear 4 and the rotation speed of the carrier Cm of the second planetary gear 5 constituting the second coupling body Cm, Ra and the ring gear Ra of the third planetary gear 6 is “0”. The carrier Cf of the first planetary gear 4 constituting the first coupling body Cf, Sm and the sun gear Sm of the second planetary gear 5 rotate at the same speed, and the second planetary gear 5 constituting the third coupling body Rm, Ca, Rr. The ring gear Rm, the carrier Ca of the third planetary gear 6 and the ring gear Rr of the fourth planetary gear 7 rotate at the same speed. Rotational speed of a line carrier Cr of the fourth planetary gear 7 is positioned which is connected to the output gear 3 becomes "1st", first speed ratio is established.

  When the third clutch C3, the first brake B1, and the second brake B2 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 are “1”, and the first coupling body Cf, The rotational speeds of the carrier Cf of the first planetary gear 4 constituting the Sm, the sun gear Sm of the second planetary gear 5, the carrier Cm of the second planetary gear 5 constituting the second coupling body Cm, Ra, and the ring gear Ra of the third planetary gear 6 are “ 0 "and the ring gear Rm of the second planetary gear 5, the carrier Ca of the third planetary gear 6, and the ring gear Rr of the fourth planetary gear 7 constituting the third coupling body Rm, Ca, Rr rotate at the same speed, The rotation speed of the fourth planetary gear 7 connected to the output gear 3 on the line where the carrier Cr is located is “2nd”. Now, the second gear is established.

  When the second clutch C2, the third clutch C3 and the second brake B2 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4, the sun gear Sa of the third planetary gear 6, and the sun gear Sr of the fourth planetary gear 7 are "1". The rotational speeds of the carrier Cm of the second planetary gear 5 and the ring gear Ra of the third planetary gear 6 constituting the second coupling body Cm, Ra become “0” and the first coupling body Cf, Sm is constituted. The carrier Cf of the planetary gear 4 and the sun gear Sm of the second planetary gear 5 rotate at the same speed, and the ring gear Rm of the second planetary gear 5 and the carrier Ca and the third planetary gear 6 of the third planetary gear 6 constituting the third coupling body Rm, Ca, Rr. The fourth planetary gear connected to the output gear 3 by rotating at a constant speed with the ring gear Rr of the four planetary gear 7 Rotational speed of a line carrier Cr is located in becomes "3rd", the third speed ratio is established.

  When the second clutch C2, the third clutch C3, and the first brake B1 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4, the sun gear Sa of the third planetary gear 6, and the sun gear Sr of the fourth planetary gear 7 are "1". ”, The rotational speeds of the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling body Cf and Sm become“ 0 ”, and the second coupling body Cm and Ra constitute the second coupling body Cm and Ra. The carrier Cm of the planetary gear 5 and the ring gear Ra of the third planetary gear 6 rotate at the same speed, and the ring gear Rm of the second planetary gear 5 and the carrier Ca and the third planetary gear 6 of the third planetary gear 6 constituting the third coupling body Rm, Ca, Rr. The fourth planetary gear connected to the output gear 3 by rotating at a constant speed with the ring gear Rr of the four planetary gear 7 Rotational speed of a line carrier Cr is located in becomes "4th", the fourth speed stage is established.

  When the second clutch C2, the third clutch C3, and the third brake B3 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4, the sun gear Sa of the third planetary gear 6, and the sun gear Sr of the fourth planetary gear 7 are "1". ”, The rotational speed of the sun gear Sf of the first planetary gear 4 becomes“ 0 ”, and the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling bodies Cf and Sm are at the same speed. The carrier Cm of the second planetary gear 5 constituting the second connecting body Cm, Ra and the ring gear Ra of the third planetary gear 6 are rotated at the same speed, and the second connecting body Rm, Ca, Rr is constituted. The ring gear Rm of the planetary gear 5, the carrier Ca of the third planetary gear 6, and the ring gear Rr of the fourth planetary gear 7 are at constant speed. Rotation to the rotational speed of a line carrier Cr of the fourth planetary gear 7 is positioned which is connected to the output gear 3 becomes "5th", the fifth gear is established.

  When the first clutch C1, the second clutch C2, and the third clutch C3 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 become “1”, and the second connection The second planetary gear 5, the third planetary gear 6, and the fourth planetary gear 7 are relatively connected by connecting the carrier Cm of the second planetary gear 5 constituting the body, the ring gear Ra of the third planetary gear 6, and the sun gear Sa of the third planetary gear 6. The rotation speed of the fourth planetary gear 7 connected to the output gear 3 on the line where the carrier Cr is located is also “6th” of “1”, and the sixth speed is established.

  When the first clutch C1, the third clutch C3, and the third brake B3 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4, the carrier Cm of the second planetary gear 5, and the sun gear Sr of the fourth planetary gear 7 are "1". ”, The rotational speed of the sun gear Sf of the first planetary gear 4 becomes“ 0 ”, and the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling bodies Cf and Sm are at the same speed. The carrier Cm of the second planetary gear 5 constituting the second connecting body Cm, Ra and the ring gear Ra of the third planetary gear 6 are rotated at the same speed, and the second connecting body Rm, Ca, Rr is constituted. The ring gear Rm of the planetary gear 5, the carrier Ca of the third planetary gear 6, and the ring gear Rr of the fourth planetary gear 7 are at constant speed. Rotation to the rotational speed of a line carrier Cr of the fourth planetary gear 7 is positioned which is connected to the output gear 3 is "7th", seventh gear is established.

  When the first clutch C1, the third clutch C3, and the first brake B1 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4, the carrier Cm of the second planetary gear 5, and the sun gear Sr of the fourth planetary gear 7 are "1". ”, The rotation speed of the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 becomes“ 0 ”, and the carrier Cm of the second planetary gear 5 and the third planetary gear 6 constituting the second coupling bodies Cm, Ra. The ring gear Ra of the second planetary gear 5 and the carrier Ca of the third planetary gear 6 and the ring gear Rr of the fourth planetary gear 7 constituting the third coupling bodies Rm, Ca, Rr rotate at the same speed. At the line where the carrier Cr of the fourth planetary gear 7 connected to the output gear 3 is located. Rotation speed is "8th", 8-speed stage is established.

  When the first clutch C1, the second brake B2, and the third brake B3 are engaged, the rotational speed of the ring gear Rf of the first planetary gear 4 is “1”, the sun gear Sf of the first planetary gear 4 and the second coupling body Cm, The rotational speeds of the carrier Cm of the second planetary gear 5 constituting the Ra and the ring gear Ra of the third planetary gear 6 become “0”, and the carrier Cf of the first planetary gear 4 constituting the first coupling bodies Cf and Sm and the second The sun gear Sm of the planetary gear 5 rotates at the same speed, and the ring gear Rm of the second planetary gear 5, the carrier Ca of the third planetary gear 6 and the ring gear Rr of the fourth planetary gear 7 constituting the third coupling bodies Rm, Ca, Rr. Rotational speed at the line where the carrier Cr of the fourth planetary gear 7 that rotates at a constant speed and is connected to the output gear 3 is located. Is "Rev" of the negative, the reverse gear is established.

  FIG. 1B is a diagram collectively showing the relationship between the above-described shift speeds and the engagement states of the clutches C1 to C3 and the brakes B1 to B3, and “◯” represents engagement. FIG. 1B shows that the gear ratio i of the first planetary gear 4 is 1.65, the gear ratio j of the second planetary gear 5 is 2.33, the gear ratio k of the third planetary gear 6 is 2.20, Also shown are the gear ratios of the respective speeds (the rotational speed of the input shaft 2 / the rotational speed of the output gear 3) when the gear ratio m of the planetary gear 7 is 1.65. According to this, the common ratio (ratio of the gear ratio between the respective gears) becomes appropriate, and the ratio orange (ratio of the first gear ratio to the eighth gear ratio (the first gear stage in FIG. 1B) Displayed in the column to the right of the gear ratio)) is also appropriate, and the shift merchantability is excellent.

  According to the first embodiment, the three clutches C1 to C3 and the three brakes B1 to B3 can secure a shift of eight forward speeds and one reverse speed, and the automatic transmissions described in Patent Documents 1 and 2 above. As compared with the above, the number of clutches arranged on the main shaft can be reduced by one. Therefore, the overall length of the automatic transmission can be shortened, and the mountability to the FF vehicle is improved.

In each shift stage, the number of engagement elements to be released is all three, and the number of engagement elements to be released is one compared to the automatic transmissions described in Patent Documents 1 and 2 above. Can be reduced. Therefore, friction loss due to drag is reduced, and transmission efficiency of the automatic transmission is improved. Further, since the first to fourth planetary gears 4 to 7 are all constituted by single-pinion type planetary gears, the gear engagement between the pinion gears in the planetary gears is made as compared with the case where the double-pinion type planetary gears are included. Can be reduced. Therefore, the meshing efficiency of the gear is improved, and the transmission efficiency of the automatic transmission is further improved.
[Second Embodiment]
Next, a second embodiment of the automatic transmission according to the present invention will be described with reference to FIGS. This automatic transmission has good mountability for FF vehicles, and is positioned around the input shaft 2 in the transmission case 1 so that the first planetary gear 4 for input and the second planetary gear for input. 5 and a third planetary gear 6 for shifting, and a fourth planetary gear 7 for output are arranged.

  The 1st planetary gear 4 is comprised with the single pinion type single planetary gear similarly to 1st Embodiment.

  The double planetary gear is composed of a second planetary gear 5 and a third planetary gear 6. Unlike the first embodiment, the second embodiment is a Ravigneaux type double planetary gear. The second planetary gear 5 is composed of a single planetary gear that includes a sun gear Sm, a ring gear Rm, and a carrier Cm that supports the pinion Pm that meshes with the sun gear Sm and the ring gear Rm so as to rotate and revolve. 6 is composed of a double pinion planetary gear comprising a sun gear Sa, a ring gear Ra, and a carrier Ca that supports a pair of pinions Pa and Pa 'meshing with the ring gear Ra, one of which is engaged with the ring gear Ra. Has been.

  The pinion Pm of the second planetary gear 5 and the pinion Pa of the third planetary gear 6 are integrated as a pinion Pm (Pa), and the carrier Cm of the second planetary gear 5 and the carrier Ca of the third planetary gear 6 are combined with the carrier Cm. It is integrated as (Ca) and supports the pinion Pm (Pa) so as to freely rotate and revolve. The ring gear Rm of the second planetary gear 5 and the ring gear Ra of the third planetary gear 6 are integrated as a ring gear Rm (Ra).

  Referring to the speed diagram of the double planetary gear shown in the middle of FIG. 2, the three elements including the sun gear Sm, the carrier Cm, and the ring gear Rm of the second planetary gear 5 are arranged at intervals corresponding to the gear ratio in the speed diagram. Assuming that the fourth element, the fifth element, and the sixth element are arranged in order from the left side, the fourth element is the sun gear Sm, the fifth element is the carrier Cm, and the sixth element is the ring gear Rm. The ratio between the distance between the sun gear Sm and the carrier Cm and the distance between the carrier Cm and the ring gear Rm is set to j: 1 where j is the gear ratio of the second planetary gear 5.

  Further, referring to the speed diagram of the above-mentioned planetary gear, the three elements including the sun gear Sa, the carrier Ca, and the ring gear Ra of the third planetary gear 6 are arranged in the order in the order corresponding to the gear ratio in the speed diagram. Are the seventh element, the eighth element, and the ninth element, respectively, the seventh element is the carrier Ca, the eighth element is the ring gear Ra, and the ninth element is the sun gear Sa. The ratio between the distance between the sun gear Sa and the carrier Ca and the distance between the carrier Ca and the ring gear Ra is set to k: 1 where k is the gear ratio of the third planetary gear 6.

  The 4th planetary gear 7 is comprised with the single pinion type single planetary gear similarly to 1st Embodiment.

  Here, the input shaft 2 is connected to the ring gear Rf (third element) of the first planetary gear 4, and the carrier Cf (second element) of the first planetary gear 4 and the sun gear Sm (fourth element) of the second planetary gear 5 are connected. Connected to form the first connected body Cf, Sm, and the ring gear Rm (Ra) (sixth element, eighth element) of the double planetary gear and the ring gear Rr (tenth element) of the fourth planetary gear 7 are connected. The third coupling bodies Rm (Ra) and Rr are configured, and the carrier Cr (11th element) of the fourth planetary gear 7 is coupled to the output gear 3.

  In the first embodiment, the carrier Cm (fifth element) of the second planetary gear 5 and the ring gear Ra (seventh element) of the third planetary gear 6 are coupled to form the second coupling bodies Cm, Ra. However, in the second embodiment, as described above, the carrier Cm (fifth element) of the second planetary gear 5 and the carrier Ca (seventh element) of the third planetary gear 6 are integrated as a carrier Cm (Ca) of the double planetary gear. It has become.

  In addition, three multi-plate clutches C1 to C3 and three brakes B1 to B3 are provided as engaging elements. The first clutch C1 is engaged so as to be switchable between a state in which the carrier Cm (Ca) of the double planetary gear and the sun gear Sr (the twelfth element) of the fourth planetary gear 7 are connected and a state in which the connection is cut off. C2 engages in a switchable manner between a state in which the sun gear Sa (9th element) of the third planetary gear 6 and the carrier Cr (11th element) of the fourth planetary gear 7 are connected and a state in which this connection is cut off. The clutch C3 engages in a switchable manner between a state in which the sun gear Sr (the twelfth element) of the fourth planetary gear 7 is connected to the input shaft 2 and a state in which the connection is broken.

  The first brake B1 engages in a switchable manner between a state in which the first coupling bodies Cf and Sm are fixed to the transmission case 1 and a state in which the first connection is released, and the second brake B2 is a carrier for the double planetary gear. The third brake B3 engages the sun gear Sf (first element) of the first planetary gear 4 with the transmission in a state in which Cm (Ca) is fixed to the transmission case 1 and to be released. It engages in a switchable manner between a state of fixing to the case 1 and a state of releasing the fixing.

  In the second embodiment configured as described above, when the third clutch C3, the second brake B2, and the third brake B3 are engaged, the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 rotate. The speed is “1”, the rotation speed of the sun gear Sf of the first planetary gear 4 and the carrier Cm (Ca) of the double planetary gear is “0”, and the carrier Cf of the first planetary gear 4 constituting the first coupling bodies Cf and Sm. And the sun gear Sm of the second planetary gear 5 rotate at the same speed, and the ring gear Rm (Ra) of the double planetary gear and the ring gear Rr of the fourth planetary gear 7 constituting the third coupling bodies Rm (Ra), Rr are at the same speed. The rotation speed of the fourth planetary gear 7 connected to the output gear 3 on the line where the carrier Cr is located is “1st Now, the first speed stage is established.

  When the third clutch C3, the first brake B1, and the second brake B2 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 are “1”, and the first coupling body Cf, The rotational speeds of the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 and the carrier Cm (Ca) of the double planetary gear constituting the Sm become “0”, and the third coupling bodies Rm (Ra) and Rr are The rotational speed of the fourth planetary gear 7 connected to the output gear 3 at the line where the carrier Cr is located is such that the ring gear Rm (Ra) of the compound planetary gear and the ring gear Rr of the fourth planetary gear 7 rotate at the same speed. “2nd” is set, and the second gear is established.

  When the second clutch C2, the third clutch C3 and the second brake B2 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 are “1”, and the carrier Cm ( As the rotational speed of Ca) becomes “0”, the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling bodies Cf and Sm rotate at the same speed, and the third coupling body. The ring gear Rm (Ra) of the double planetary gear constituting Rm (Ra), Rr and the ring gear Rr of the fourth planetary gear 7 rotate at the same speed, and the sun gear Sa of the third planetary gear 6 and the carrier Cr of the fourth planetary gear 7 Rotational speed of the fourth planetary gear 7 that rotates at a constant speed and is connected to the output gear 3 on the line where the carrier Cr is located Becomes "3rd", the third speed stage is established.

  When the second clutch C2, the third clutch C3, and the first brake B1 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 are "1", the first coupling body Cf, The rotational speeds of the carrier Cf of the first planetary gear 4 constituting the Sm and the sun gear Sm of the second planetary gear 5 become “0”, and the ring gear Rm (Ra of the double planetary gear constituting the third coupling bodies Rm (Ra), Rr) ) And the ring gear Rr of the fourth planetary gear 7 rotate at the same speed, the sun gear Sa of the third planetary gear 6 and the carrier Cr of the fourth planetary gear 7 rotate at the same speed, and are connected to the output gear 3. The rotational speed of the planetary gear 7 along the line where the carrier Cr is located is “4th”, and the fourth speed stage is established.

  When the second clutch C2, the third clutch C3, and the third brake B3 are engaged, the rotational speed of the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 is "1", and the sun gear of the first planetary gear 4 is While the rotation speed of Sf becomes “0”, the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling bodies Cf and Sm rotate at the same speed, and the third coupling body Rm. The ring gear Rm (Ra) of the double planetary gear constituting (Ra), Rr and the ring gear Rr of the fourth planetary gear 7 rotate at the same speed, and the sun gear Sa of the third planetary gear 6 and the carrier Cr of the fourth planetary gear 7 are equal. The rotation speed of the fourth planetary gear 7 connected to the output gear 3 at the line where the carrier Cr is positioned is “5”. Becomes h ", 5-speed stage is established.

  When the first clutch C1, the second clutch C2, and the third clutch C3 are engaged, the rotational speeds of the ring gear Rf of the first planetary gear 4 and the sun gear Sr of the fourth planetary gear 7 become “1”, and the double planetary gear When the carrier Cm (Ca) and the sun gear Sr of the fourth planetary gear 7 are connected, the second planetary gear 5, the third planetary gear 6 and the fourth planetary gear 7 are locked in a relatively non-rotatable state and connected to the output gear 3. The rotational speed of the fourth planetary gear 7 on the line where the carrier Cr is located is also “1”, “6th”, and the sixth gear is established.

  When the first clutch C1, the third clutch C3, and the third brake B3 are engaged, the rotational speed of the ring gear Rf of the first planetary gear 4, the carrier Cm (Ca) of the double planetary gear, and the sun gear Sr of the fourth planetary gear 7 is " 1 ”, the rotational speed of the sun gear Sf of the first planetary gear 4 becomes“ 0 ”, and the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling bodies Cf and Sm are at the same speed. And the ring gear Rm (Ra) of the dual planetary gear constituting the third coupling body Rm (Ra), Rr and the ring gear Rr of the fourth planetary gear 7 rotate at the same speed and are coupled to the output gear 3. The rotational speed at the line where the carrier Cr of the 4-planetary gear 7 is located is “7th”, and the seventh speed stage is established.

  When the first clutch C1, the third clutch C3, and the first brake B1 are engaged, the rotational speed of the ring gear Rf of the first planetary gear 4, the carrier Cm (Ca) of the double planetary gear, and the sun gear Sr of the fourth planetary gear 7 is " 1 ”, the rotational speeds of the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling bodies Cf, Sm become“ 0 ”, and the third coupling bodies Rm (Ra), Rr The rotational speed of the fourth planetary gear 7 connected to the output gear 3 at the line where the carrier Cr is located is such that the ring gear Rm (Ra) of the compound planetary gear and the ring gear Rr of the fourth planetary gear 7 rotate at the same speed. “8th” is reached, and the eighth gear is established.

  When the first clutch C1, the second brake B2, and the third brake B3 are engaged, the rotational speed of the ring gear Rf of the first planetary gear 4 is “1”, the sun gear Sf of the first planetary gear 4 and the carrier Cm of the double planetary gear ( Ca) and the rotational speed of the sun gear Sr of the fourth planetary gear 7 become “0”, and the carrier Cf of the first planetary gear 4 and the sun gear Sm of the second planetary gear 5 constituting the first coupling bodies Cf and Sm are at the same speed. And the ring gear Rm (Ra) of the dual planetary gear constituting the third coupling body Rm (Ra), Rr and the ring gear Rr of the fourth planetary gear 7 rotate at the same speed and are coupled to the output gear 3. The rotational speed of the line where the carrier Cr of the four planetary gear 7 is located becomes negative “Rev”, and the reverse speed is established.

  FIG. 3B is a diagram collectively showing the relationship between the above-described shift speeds and the engagement states of the clutches C1 to C3 and the brakes B1 to B3, and “◯” represents engagement. 1B shows that the gear ratio i of the first planetary gear 4 is 1.50, the gear ratio j of the second planetary gear 5 is 2.15, the gear ratio k of the third planetary gear 6 is 2.05, Also shown is the gear ratio (rotational speed of the input shaft 2 / rotational speed of the output gear 3) of each gear when the gear ratio m of the planetary gear 7 is 1.60. According to this, the common ratio (ratio of the gear ratio between the respective gears) becomes appropriate, and the ratio orange (ratio of the first gear ratio to the eighth gear ratio (the first gear stage in FIG. 3B) Displayed in the column to the right of the gear ratio)) is also appropriate, and the shift merchantability is excellent.

  According to the second embodiment, the three clutches C1 to C3 and the three brakes B1 to B3 can ensure a shift of eight forward speeds and one reverse speed. And compared with the automatic transmission of the said patent document 1, 2, the number of the clutch arrange | positioned on a main shaft can be decreased by one. Therefore, the overall length of the automatic transmission can be shortened, and the mountability to the FF vehicle is improved. Further, since the Ravigneaux-type double planetary gear is configured by the second planetary gear 5 and the third planetary gear 6, the overall length of the automatic transmission can be further shortened as compared with the first embodiment.

Further, the number of engagement elements to be released is three at each shift stage, and the number of engagement elements to be released is reduced by one compared to the automatic transmissions described in Patent Documents 1 and 2 above. Can be made. Therefore, friction loss due to drag is reduced, and transmission efficiency of the automatic transmission is improved.
[Third Embodiment]
As shown in FIG. 5, the third embodiment of the automatic transmission according to the present invention replaces the third clutch C <b> 3 of the first embodiment with a multi-plate clutch, and the sun gear of the input shaft 2 and the fourth planetary gear 7. A dog clutch D that engages in a switchable manner between a state in which Sr (the twelfth element) is connected and a state in which the connection is broken is used. As a result, the structure can be simplified as compared with a multi-plate clutch, so that all the axes of the automatic transmission can be made shorter. Although not shown in detail, the dog clutch D is composed of dog teeth installed on the outer periphery of the member connected to the sun gear Sr of the fourth planetary gear 7 and a movable dog splined to the outer periphery of the input shaft. Is engaged with the dog teeth of the member connected to the sun gear Sr, and the rotation from the power source is input to the sun gear Sr. Although not shown, a synchro clutch may be used instead of the dog clutch D.
[Fourth Embodiment]
As shown in FIG. 6, in the fourth embodiment of the automatic transmission according to the present invention, the third clutch C3 of the second embodiment is replaced with a multi-plate clutch, and the input shaft 2 is similar to the third embodiment. And a dog clutch D which engages in a switchable manner between a state where the sun gear Sr (the 12th element) of the fourth planetary gear 7 is connected and a state where the connection is cut off. Thereby, since the structure can be simplified, all the axes of the automatic transmission can be made shorter. Although not shown, a synchro clutch may be used instead of the dog clutch D.
[Fifth Embodiment]
In the fifth embodiment of the automatic transmission according to the present invention, an output shaft 3 coaxial with the input shaft 2 is provided as an output member in place of the output gear 3 of the first embodiment, as shown in FIG. Thereby, it can mount suitably in FR (front engine * rear drive) vehicle mounted vertically so that the input shaft 2 of an automatic transmission may face the front-back direction of a vehicle. In addition, although not shown, the second to fourth embodiments of the automatic transmission are similarly mounted on the FR vehicle by providing the output shaft 3 coaxial with the input shaft 2 as an output member instead of the output gear 3. It may be possible.

DESCRIPTION OF SYMBOLS 1 ... Transmission case, 2 ... Input shaft (input member), 3 ... Output gear, Output shaft (output member), 4 ... 1st planetary gear, 5 ... 2nd planetary gear, 6 ... 3rd planetary gear, 7 ... 4th planetary gear , Sf: Sun gear of the first planetary gear (first element), Rf ... Ring gear of the first planetary gear (third element), Cf ... Carrier of the first planetary gear (second element), Sm ... Sun gear of the second planetary gear (fourth element) Element), Rm ... second planetary gear ring gear (sixth element), Cm ... second planetary gear carrier (fifth element), Sa ... third planetary gear sun gear (ninth element), Ra ... third planetary gear ring gear ( Seventh element), Ca ... third planetary gear carrier (eighth element), Sr ... fourth planetary gear sun gear (twelfth element), Rr ... 4 planetary gear ring gear (10th element), Cr ... 4th planetary gear carrier (11th element), Cm (Ca) ... double planetary gear carrier (5th element, 7th element), Rm (Ra) ... double planetary gear Ring gear (6th element, 8th element), C1 ... 1st clutch, C2 ... 2nd clutch, C3 ... 3rd clutch, B1 ... 1st brake, B2 ... 2nd brake, B3 ... 3rd brake, D ... Dog clutch (3rd clutch).

Claims (4)

An automatic transmission that is composed of three elements, a sun gear, a carrier, and a ring gear, and that shifts the rotation of the input member to a plurality of stages and transmits it to the output member via first to fourth planetary gears arranged in the transmission case. Because
The three elements of the first planetary gear are defined as the first element, the second element, and the third element, respectively, and the three elements of the second planetary gear are defined as the fourth element in order of arrangement at intervals corresponding to the gear ratio in the velocity diagram. The third element of the third planetary gear is the seventh element, the eighth element and the ninth element, respectively, and the three elements of the fourth planetary gear are the tenth element and the eleventh element, respectively. As element and twelfth element,
The input member is connected to the third element, the second element and the fourth element are connected to form a first connecting body, the fifth element and the seventh element are connected to form a second connecting body, The sixth element, the eighth element, and the tenth element are connected to form a third connector, and the eleventh element is connected to the output member.
A first clutch that is switchable between a state in which the second connecting body and the twelfth element are connected and a state in which the connection is broken;
A second clutch switchable between a state of connecting the ninth element and the twelfth element and a state of disconnecting the connection;
A third clutch switchable between a state of connecting the input member and the twelfth element and a state of disconnecting the connection;
A first brake switchable between a state in which the first coupling body is fixed to the transmission case and a state in which the fixing is released;
A second brake that is switchable between a state in which the second coupling body is fixed to the transmission case and a state in which the fixation is released;
An automatic transmission comprising: a third brake that is switchable between a state in which the first element is fixed to the transmission case and a state in which the first element is released. An automatic transmission that is composed of three elements, a sun gear, a carrier, and a ring gear, and that shifts the rotation of the input member to a plurality of stages and transmits it to the output member via first to fourth planetary gears arranged in the transmission case. Because
The three elements of the first planetary gear are defined as the first element, the second element, and the third element, respectively, and the three elements of the second planetary gear are defined as the fourth element in order of arrangement at intervals corresponding to the gear ratio in the velocity diagram. The third element of the third planetary gear is the seventh element, the eighth element and the ninth element, respectively, and the three elements of the fourth planetary gear are the tenth element and the eleventh element, respectively. As element and twelfth element,
The input member is connected to the third element, the second element and the fourth element are connected to form a first connecting body, the fifth element and the seventh element are connected to form a second connecting body, The sixth element, the eighth element, and the tenth element are connected to form a third connector, and the eleventh element is connected to the output member.
A first clutch that is switchable between a state in which the second connecting body and the twelfth element are connected and a state in which the connection is broken;
A second clutch switchable between a state of connecting the ninth element and the eleventh element and a state of disconnecting the connection;
A third clutch switchable between a state of connecting the input member and the twelfth element and a state of disconnecting the connection;
A first brake switchable between a state in which the first coupling body is fixed to the transmission case and a state in which the fixing is released;
A second brake that is switchable between a state in which the second coupling body is fixed to the transmission case and a state in which the fixation is released;
An automatic transmission comprising: a third brake that is switchable between a state in which the first element is fixed to the transmission case and a state in which the first element is released.   The second planetary gear and the third planetary gear are integrated by integrating the fifth element of the second planetary gear and the seventh element of the third planetary gear, and integrating the sixth element of the second planetary gear and the eighth element of the third planetary gear. The automatic transmission according to claim 1 or 2, wherein a Ravigneaux type double planetary gear is constructed.   The automatic transmission according to any one of claims 1 to 3, wherein the third clutch is a dog clutch or a synchro clutch.