CA1115991A - Tractor transmission - Google Patents
Tractor transmissionInfo
- Publication number
- CA1115991A CA1115991A CA350,219A CA350219A CA1115991A CA 1115991 A CA1115991 A CA 1115991A CA 350219 A CA350219 A CA 350219A CA 1115991 A CA1115991 A CA 1115991A
- Authority
- CA
- Canada
- Prior art keywords
- transmission case
- transmission
- brake
- case
- tractor
- 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.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T11/00—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant
- B60T11/04—Transmitting braking action from initiating means to ultimate brake actuator without power assistance or drive or where such assistance or drive is irrelevant transmitting mechanically
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60K—ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES
- B60K17/00—Arrangement or mounting of transmissions in vehicles
- B60K17/04—Arrangement or mounting of transmissions in vehicles characterised by arrangement, location, or kind of gearing
- B60K17/06—Arrangement or mounting of transmissions in vehicles characterised by arrangement, location, or kind of gearing of change-speed gearing
- B60K17/08—Arrangement or mounting of transmissions in vehicles characterised by arrangement, location, or kind of gearing of change-speed gearing of mechanical type
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T1/00—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles
- B60T1/02—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels
- B60T1/06—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels acting otherwise than on tread, e.g. employing rim, drum, disc, or transmission or on double wheels
- B60T1/062—Arrangements of braking elements, i.e. of those parts where braking effect occurs specially for vehicles acting by retarding wheels acting otherwise than on tread, e.g. employing rim, drum, disc, or transmission or on double wheels acting on transmission parts
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
- B60T7/00—Brake-action initiating means
- B60T7/02—Brake-action initiating means for personal initiation
- B60T7/08—Brake-action initiating means for personal initiation hand actuated
- B60T7/10—Disposition of hand control
- B60T7/102—Disposition of hand control by means of a tilting lever
-
- 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
- F16D65/00—Parts or details
- F16D65/14—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position
- F16D65/16—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Transportation (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Braking Arrangements (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A tractor transmission having a transmission case divided into three sections, namely front, intermediate and rear transmission cases. The intermediate transmission case is provided with a parking brake which applies a braking action to a bevel pinion shaft of a differential mechanism
A tractor transmission having a transmission case divided into three sections, namely front, intermediate and rear transmission cases. The intermediate transmission case is provided with a parking brake which applies a braking action to a bevel pinion shaft of a differential mechanism
Description
~591~'3L
The present invention relates to a tractor -trans-mission .
A tractor has brake means to apply a braking action directly to wheels as does an ordinary vehicle~ In countxies where the law so requires, or when used a-t certain special work sites, -tractors mus-t be equipped with a parking brake which is operable independently of the above mentioned brake means.
Parking brakes o:f ordinary vehicles are usually a:rranged to ac-t directly on a drive shaE-t for driving wheels or on a change speed shaft operatively connected to the d:rive shaf-t. Tractors, on the other hand, are constructed with means -to provide multiple speeds in order to carry ou-t va:ried operations and therefor~ have a complicated transmission. It is no easy matter to incorporate a parking brake mechan:ism into such a transmissiorl.
Moreover, unlike ordinary vehicles, the tractor has a -transmission case per se forming part oE its body frame, and its bod~ length or wheelbase is usually adjusted by al-tering the length of the transmission case. Therefore, different transmission cases have to be designed when manufacturing tractors of different wheelbases, which has been a cause of the high cost of tractors. Thus, there is a demand for a transmisslon case applicable to various trac-tors.
The object of the present invention is -to provide a tractor transmission adapted for various -types of tracto:rs and for allowing a parking brake to be lnclucled.
The tractor transmissionaccording to this invention comprises a front transmission case connected to a clu-tch 0 housing and containing a main change speed mechanism, a rear i tr~nsmission case containing a differential mechanism ancl an auxiliary change speed mechanism, an in-termedia-te -transmission case disposed between and coupliny the front -transmission case and the rear transmission case, a first travelliny system transmlssion shaft mounted in -the front transm:Lss:ion case, a second travelling system transmission shaft mounted in the rear translmission cas~, couplincJ ~leans coupli.rl(~ the two travelling system transrnission shafts, d first power takeoff system -transmission shaft mounted in the front trans-mission case, a second power takeoff system transmiss:Lon shaf-t mounted in the rear-transmi.ssion case, coupling means coupling the two power -takeoff system transmission shafts, a beve:L
pinion shaf-t of -the differential mechanism moun-ted in the rear -transmission case and having one end thereof p:ro-truding into -the intermediate transmission case, a brake drum secured to the one end of the bevel pinion shaf-t protruding .into the intexmediate transmission case, and b.rake means provided on the intermediate transmission case and adapted to press against the brake drum.
More particularly, the present inven-tion divides the transmlssion case and also the transmission shafts of the travelling system and of the power takeoff system in-to front and rear sections, and inserts anintermediate trans-mission case therebetween. This arranyemerlt permi.ts -the wheel.base to be adjusted as desired by uslny an i.ntermediate case oE suitable lenyth. Thus, the transmission case long-itudinally divided as described above may be usecl for varied types of tractors, and at -the same -time -the intermecliate case is used to accommodate brake means.
In other worcls, the present invention provides for wheelbase adjustment and mounting of parkincJ brake mear~s by introducing the ln-termediate -transmission case. 'I`he ir.vention has realized a transmission case adapted for varied types of tractors which may be manufactured at low cost and at the same time having parking brake means incorporated -therein.
O-ther objec-ts and advan-tages oE this i:[lVellt:iOII will be apparell-t from -the Eollow:ing description.
'I`he invention will now be more particular:Ly describecl wi-th reference to embodimen-ts thereof shown, by way oE example, in -the accompanying drawings, in whieh:
Fig. 1 is a side view of an agricultural trac-tor having a -transmission according to the present inven-tion;
Fig. 2 is a fragmentary side view in vertical sec-tion of the transmission showing the loca-tion of a clrive pinion shaft;
Fig. 3 is a ~ragmentary side view of the transmission showing the location of a lever for operating parking brake means;
Fiy. 4 is a front view of a brake mechanism con-nected to the lever of Fig~ 3;
Fig. 5 is a Eragmentary side view, partly in ver-tieal sec-tion, showing the loeation of a cam member in the brake mechanism of Fig. 4;
E`ig. 6 is a fragmentary side view of -the trc~nsmission showincJ the location of a lever for opera-ting parklng brake means according to a modified embodimenti and Fig. 7 is a seetional view -taken along the line Vll-Vll oE E`ig. 6.
Fic~ 1 is a side view of an agricultural tractor which has an engine 1, a clutch housing 2, a tubular front tr~nsmissiorl case 3 contain.ing a gear chanc~e speecl~llechanism to change t.ravelling speed, namely a main speed c~lange mechanism (not shown), a tubular in-termediate transrnission case 5 provided with a br~ke means 4 descr:ibed later, and a tubular rear transmission case 7 containing a differen-tial mechanism 6 (Fig.~) for rear wheels, each case being connected to an adjacent case -to forrn an elonga-ted frame extend:lncJ long-itudinally of the tractor. A pair of riyht and left fxont, wheels 8, 8 are disposed below and on bo-th lateral sides of the engine 1, and a pair of righ-t and left rear wheels 9, 9 are a-ttached directly to the rear transmissi.on case 7.
Number 10 denotes a driver's seat mounted on the rear -transmission case 7. Number 11 denotes a steering wheel disposed forwardly of the drive.r's sea-t 10 to change direction of -the front wheels 8, 8. Number 12 denotes a travelling speed change lever projec-ting from the top of the fron-t transmission case 3~ Number 14 denotes a lever attached to the top of the intermediate transmission case 5 for operating the brake means.
rrhe brake means 4 which is used mainly during parking will now be described with reference to Figs. 2, 3, 4 and 5.
The differential mechanism 6 has a drive pinion shaft 15 projecting into theintermediate transmi.ssion case 5, and the end of the drive pinion shaft 15 lying in the intermedia-te transmiss.i.on case 5 carries fixed -thereto a disc shapecl braklng action receiving member or brake drum 4a of the brake means 4.
Braking members 4b, 4b axe fixed to upper and :Lower inner peripheries of a C shaped leaf spring 17 which ic; re-siliently and tranversely movably supported by a bracket 16 59~
li.Y~d to Oll~ ld-teral wall of the interrnediate transmission case 5. Ends of the C-shaped leaf spring 17 are penetrated by an operator rod 18 extending throuyh a bracket 36 fixed to -th$ other lat~al wall of -the intermediate transmission case 5. The operator rod 18 has a nut 19 screwed -to an upper end thereof to receive the back of the upper end of the C-sha~ed leaf spring 17/ and a cam member 20 pivoted to a lower end thereof to press and displace the lower end of -the C-shaped leaf spring 17 upwardly. ~ rotatable cross rod 21 ls pro-vided to extend transversely through the other wall of the intermediate transmission case 5. Part of the rod ~1 lying inside the case 5 carries fixed there-to a cam operator 22 to press and oscillate -che cam member 20, and part of the rod 21 lying outside the case 5 carries an oscillatable arm 23 fixed thereto. The arm 23 is operatively connected to -the brake operating laver 14 through a rod 24. The lever 14 is vertically oscillatably pivoted to a support frame 25 a-ttached to the intermediate transmission case 5. A ra-tche-t mechanism 26 comprising a ratchet pawl 26a and a lock receiving member 26b is provided to lock the lever 14 at a desired position. The lever 14 has a press elemen-t 27 at an extre~le end of its yrip portion to cause oscillation of the ratchet pawl 26a.
According to the above construction, when the lever 14 is pulled upward, the ends of the C-shaped leaf .sprincJ 17 are moved towards each other whereby the cam member 20 causes the braking members 4b, 4b to contact the brake drum 4a to provide braking~ and when the lever 14 is oscillated downward -the braking is released.
In Fig. 2, number 28 denotes a slide gear splined ~S~
Lo the drive pinion shaft 15. ~rive is subjected to speed chanc~ing in -the fron-t transmission case 3 and is passed to a second travelling system transmission shaf-t 29b. Outpu-t of the transmission shaft 29b is transferred in two speeds by the slide gear 28 to the drive pinion shaf-t 15. This ar-rangement for providing the two step speed change is referred to herein as auxiliary change speed mechanism 37. The second travelling system transmission shaEt 29b is coupled by a coupling 29c to afirst travelling sys-tem transmission shaft 29a extending from the above-mentioned main change speed mechanism (no-t shown) provided in the front transmission case 3. In other words, the transmission shaft of the tra-velling system is divided into two sections to correspond -to the front, rear and intermediate transmission cases 3 r 7 and 5.
Number 30a denotes a first transmission shaft o~ a power -takeoff system taking power from an input side of the main change speed mechanism (no-t shown~ in the front trans-miss:ion case 3~ Number 30b denotes a second power -takeoff transmission shaft mounted in the rear transmiss,ion case 7 and coupled to the first power takeofE -transmission shaft 30a by a coupling 30c. Number 31a is a third power takeoEf transmission shaft coupled to the second power takeoff trans-mission shaft 30b by a coupliny 31b and adap-ted -to transmi-t power to a rearmost power takeoff shaft 32 at a rear end of the trac-tor. It will be understood that -the power -takeoff s~stem comprises the firs-t and second transmission shafts correspondiny to the plural transmission cases 3, 5 and 7 as does the travelling system. Number 33 deno-tes a transmission shaEt for driving the front wheels which is placed into and ~5~3~
out of operati.ve connec-tion with the drive pinion shaf-t 15 by operating a slide geax 34.
The brake means adapted to app:Ly a braking action to the drive pinion shaft by pressing a pair of braking members against the outer periphery of a bra]ce drum as de~
scribed above re~uires a small space longitudinal.ly of -the tractor and fits compactly into the intermediate transm~ission case 5, compared with an in-ternally acting brake mechanism wherein cam opera-ting shafts for actuating braking members extend .~orwa.rdly or rearwardly of the brake drum. Furthermo:re, ~in~e ~ht' br~ing members 4b, 4bare pressed against the brake drum 4a by using the cam mernber, reliable brakincJ is assured.
A modified brake means used mainly during parking is described next wlth reference to Figs. 6 and 7. The com-ponent elements alxeady described in connection with the firs-t embodiment are described hereinbelow using like reference numbers.
A drive pinion shaft 15 of differen-tial means (not shown) projects into an intermediate transmission case 5, and the end of the drive pinion shaft 15 lying in the in-te:rmedi.ate transmission case 5 carries ixed thereto a disc shaped braking action receiving member or brake drum 4a of the brake means 4.
A pair of upper and lower braking members 104b, 104b are vertically oscillatably pivoted to a side wall oE the intermediate transmission case 5. The b:raking members 4b, 4b are ad~pted to press against the outer periphery of the brake drum ~a to thereby apply a braking ac-tion to the drive pinion shaft 15.
3~ A pair of upper and lower rotatable rods 116a, 1.16b exterlds transversely through the o-ther side wall of the inter~
mediate transmission case 5. Parts of these rota-table rods 116a, 116b lyiny inside the case 5 have secured theretc cam members 117a, 117b to press the pair of braking members 104b, 104b ayainst the brake drum 4a, respectively. ~art of the lower rotatable rod 115b :Lying outside t.he case S has fixed thereto an oscil:latable arm 1:l~. The arln :L:L8 .i.s o~.)erati~ely connected to the brake operating lever 14 by way of the rod 24. Par-t of the uppe:r rotatabl.e rod 116a lying ou-tside the :L0 case 5 has fixed there-to an oscillatable arm 120 which is operatively connected to -the arm 118 -through a rod 121. The lever 1.4 is vertically oscillatably pivo-ted to a suppo.rt frcllrle 25 attached to -the intermedia-te transmission case 5. A
ratchet mechanism 26 comprising a ratche-t pawl 26a and a lock receiving member 26b is provided to lock -the lever 1~ at a desired position. The lever 14 has a press elemen-t 27 at an extreme end of its grip portion to cause oscillation of the ratche-t pawl 26a.
According to the above construc-tion, when the lcver 14 is pulled upward, the cam members 117a, 117b cause brakiny members 104b, 104b to con-tact the brake drum 4a -to provide braking, and when the lever 14 is oscilla-ted downward the braking is released.
The hrake means adapted -to apply a braking action to the drive pinion shaft by pressing a pair of braking melrlbers against the outer periphery oE a bra]ce drum as described above has an advantage over an internally acting brake mechan-ism wherein cam operating sha:Ets for actuating braking members extend forwardly or rearwardly of -the brake drum, in that the former may be fit-ted compactly withou-t requiring a large longitudinal space.
The present invention relates to a tractor -trans-mission .
A tractor has brake means to apply a braking action directly to wheels as does an ordinary vehicle~ In countxies where the law so requires, or when used a-t certain special work sites, -tractors mus-t be equipped with a parking brake which is operable independently of the above mentioned brake means.
Parking brakes o:f ordinary vehicles are usually a:rranged to ac-t directly on a drive shaE-t for driving wheels or on a change speed shaft operatively connected to the d:rive shaf-t. Tractors, on the other hand, are constructed with means -to provide multiple speeds in order to carry ou-t va:ried operations and therefor~ have a complicated transmission. It is no easy matter to incorporate a parking brake mechan:ism into such a transmissiorl.
Moreover, unlike ordinary vehicles, the tractor has a -transmission case per se forming part oE its body frame, and its bod~ length or wheelbase is usually adjusted by al-tering the length of the transmission case. Therefore, different transmission cases have to be designed when manufacturing tractors of different wheelbases, which has been a cause of the high cost of tractors. Thus, there is a demand for a transmisslon case applicable to various trac-tors.
The object of the present invention is -to provide a tractor transmission adapted for various -types of tracto:rs and for allowing a parking brake to be lnclucled.
The tractor transmissionaccording to this invention comprises a front transmission case connected to a clu-tch 0 housing and containing a main change speed mechanism, a rear i tr~nsmission case containing a differential mechanism ancl an auxiliary change speed mechanism, an in-termedia-te -transmission case disposed between and coupliny the front -transmission case and the rear transmission case, a first travelliny system transmlssion shaft mounted in -the front transm:Lss:ion case, a second travelling system transmission shaft mounted in the rear translmission cas~, couplincJ ~leans coupli.rl(~ the two travelling system transrnission shafts, d first power takeoff system -transmission shaft mounted in the front trans-mission case, a second power takeoff system transmiss:Lon shaf-t mounted in the rear-transmi.ssion case, coupling means coupling the two power -takeoff system transmission shafts, a beve:L
pinion shaf-t of -the differential mechanism moun-ted in the rear -transmission case and having one end thereof p:ro-truding into -the intermediate transmission case, a brake drum secured to the one end of the bevel pinion shaf-t protruding .into the intexmediate transmission case, and b.rake means provided on the intermediate transmission case and adapted to press against the brake drum.
More particularly, the present inven-tion divides the transmlssion case and also the transmission shafts of the travelling system and of the power takeoff system in-to front and rear sections, and inserts anintermediate trans-mission case therebetween. This arranyemerlt permi.ts -the wheel.base to be adjusted as desired by uslny an i.ntermediate case oE suitable lenyth. Thus, the transmission case long-itudinally divided as described above may be usecl for varied types of tractors, and at -the same -time -the intermecliate case is used to accommodate brake means.
In other worcls, the present invention provides for wheelbase adjustment and mounting of parkincJ brake mear~s by introducing the ln-termediate -transmission case. 'I`he ir.vention has realized a transmission case adapted for varied types of tractors which may be manufactured at low cost and at the same time having parking brake means incorporated -therein.
O-ther objec-ts and advan-tages oE this i:[lVellt:iOII will be apparell-t from -the Eollow:ing description.
'I`he invention will now be more particular:Ly describecl wi-th reference to embodimen-ts thereof shown, by way oE example, in -the accompanying drawings, in whieh:
Fig. 1 is a side view of an agricultural trac-tor having a -transmission according to the present inven-tion;
Fig. 2 is a fragmentary side view in vertical sec-tion of the transmission showing the loca-tion of a clrive pinion shaft;
Fig. 3 is a ~ragmentary side view of the transmission showing the location of a lever for operating parking brake means;
Fiy. 4 is a front view of a brake mechanism con-nected to the lever of Fig~ 3;
Fig. 5 is a Eragmentary side view, partly in ver-tieal sec-tion, showing the loeation of a cam member in the brake mechanism of Fig. 4;
E`ig. 6 is a fragmentary side view of -the trc~nsmission showincJ the location of a lever for opera-ting parklng brake means according to a modified embodimenti and Fig. 7 is a seetional view -taken along the line Vll-Vll oE E`ig. 6.
Fic~ 1 is a side view of an agricultural tractor which has an engine 1, a clutch housing 2, a tubular front tr~nsmissiorl case 3 contain.ing a gear chanc~e speecl~llechanism to change t.ravelling speed, namely a main speed c~lange mechanism (not shown), a tubular in-termediate transrnission case 5 provided with a br~ke means 4 descr:ibed later, and a tubular rear transmission case 7 containing a differen-tial mechanism 6 (Fig.~) for rear wheels, each case being connected to an adjacent case -to forrn an elonga-ted frame extend:lncJ long-itudinally of the tractor. A pair of riyht and left fxont, wheels 8, 8 are disposed below and on bo-th lateral sides of the engine 1, and a pair of righ-t and left rear wheels 9, 9 are a-ttached directly to the rear transmissi.on case 7.
Number 10 denotes a driver's seat mounted on the rear -transmission case 7. Number 11 denotes a steering wheel disposed forwardly of the drive.r's sea-t 10 to change direction of -the front wheels 8, 8. Number 12 denotes a travelling speed change lever projec-ting from the top of the fron-t transmission case 3~ Number 14 denotes a lever attached to the top of the intermediate transmission case 5 for operating the brake means.
rrhe brake means 4 which is used mainly during parking will now be described with reference to Figs. 2, 3, 4 and 5.
The differential mechanism 6 has a drive pinion shaft 15 projecting into theintermediate transmi.ssion case 5, and the end of the drive pinion shaft 15 lying in the intermedia-te transmiss.i.on case 5 carries fixed -thereto a disc shapecl braklng action receiving member or brake drum 4a of the brake means 4.
Braking members 4b, 4b axe fixed to upper and :Lower inner peripheries of a C shaped leaf spring 17 which ic; re-siliently and tranversely movably supported by a bracket 16 59~
li.Y~d to Oll~ ld-teral wall of the interrnediate transmission case 5. Ends of the C-shaped leaf spring 17 are penetrated by an operator rod 18 extending throuyh a bracket 36 fixed to -th$ other lat~al wall of -the intermediate transmission case 5. The operator rod 18 has a nut 19 screwed -to an upper end thereof to receive the back of the upper end of the C-sha~ed leaf spring 17/ and a cam member 20 pivoted to a lower end thereof to press and displace the lower end of -the C-shaped leaf spring 17 upwardly. ~ rotatable cross rod 21 ls pro-vided to extend transversely through the other wall of the intermediate transmission case 5. Part of the rod ~1 lying inside the case 5 carries fixed there-to a cam operator 22 to press and oscillate -che cam member 20, and part of the rod 21 lying outside the case 5 carries an oscillatable arm 23 fixed thereto. The arm 23 is operatively connected to -the brake operating laver 14 through a rod 24. The lever 14 is vertically oscillatably pivoted to a support frame 25 a-ttached to the intermediate transmission case 5. A ra-tche-t mechanism 26 comprising a ratchet pawl 26a and a lock receiving member 26b is provided to lock the lever 14 at a desired position. The lever 14 has a press elemen-t 27 at an extre~le end of its yrip portion to cause oscillation of the ratchet pawl 26a.
According to the above construction, when the lever 14 is pulled upward, the ends of the C-shaped leaf .sprincJ 17 are moved towards each other whereby the cam member 20 causes the braking members 4b, 4b to contact the brake drum 4a to provide braking~ and when the lever 14 is oscillated downward -the braking is released.
In Fig. 2, number 28 denotes a slide gear splined ~S~
Lo the drive pinion shaft 15. ~rive is subjected to speed chanc~ing in -the fron-t transmission case 3 and is passed to a second travelling system transmission shaf-t 29b. Outpu-t of the transmission shaft 29b is transferred in two speeds by the slide gear 28 to the drive pinion shaf-t 15. This ar-rangement for providing the two step speed change is referred to herein as auxiliary change speed mechanism 37. The second travelling system transmission shaEt 29b is coupled by a coupling 29c to afirst travelling sys-tem transmission shaft 29a extending from the above-mentioned main change speed mechanism (no-t shown) provided in the front transmission case 3. In other words, the transmission shaft of the tra-velling system is divided into two sections to correspond -to the front, rear and intermediate transmission cases 3 r 7 and 5.
Number 30a denotes a first transmission shaft o~ a power -takeoff system taking power from an input side of the main change speed mechanism (no-t shown~ in the front trans-miss:ion case 3~ Number 30b denotes a second power -takeoff transmission shaft mounted in the rear transmiss,ion case 7 and coupled to the first power takeofE -transmission shaft 30a by a coupling 30c. Number 31a is a third power takeoEf transmission shaft coupled to the second power takeoff trans-mission shaft 30b by a coupliny 31b and adap-ted -to transmi-t power to a rearmost power takeoff shaft 32 at a rear end of the trac-tor. It will be understood that -the power -takeoff s~stem comprises the firs-t and second transmission shafts correspondiny to the plural transmission cases 3, 5 and 7 as does the travelling system. Number 33 deno-tes a transmission shaEt for driving the front wheels which is placed into and ~5~3~
out of operati.ve connec-tion with the drive pinion shaf-t 15 by operating a slide geax 34.
The brake means adapted to app:Ly a braking action to the drive pinion shaft by pressing a pair of braking members against the outer periphery of a bra]ce drum as de~
scribed above re~uires a small space longitudinal.ly of -the tractor and fits compactly into the intermediate transm~ission case 5, compared with an in-ternally acting brake mechanism wherein cam opera-ting shafts for actuating braking members extend .~orwa.rdly or rearwardly of the brake drum. Furthermo:re, ~in~e ~ht' br~ing members 4b, 4bare pressed against the brake drum 4a by using the cam mernber, reliable brakincJ is assured.
A modified brake means used mainly during parking is described next wlth reference to Figs. 6 and 7. The com-ponent elements alxeady described in connection with the firs-t embodiment are described hereinbelow using like reference numbers.
A drive pinion shaft 15 of differen-tial means (not shown) projects into an intermediate transmission case 5, and the end of the drive pinion shaft 15 lying in the in-te:rmedi.ate transmission case 5 carries ixed thereto a disc shaped braking action receiving member or brake drum 4a of the brake means 4.
A pair of upper and lower braking members 104b, 104b are vertically oscillatably pivoted to a side wall oE the intermediate transmission case 5. The b:raking members 4b, 4b are ad~pted to press against the outer periphery of the brake drum ~a to thereby apply a braking ac-tion to the drive pinion shaft 15.
3~ A pair of upper and lower rotatable rods 116a, 1.16b exterlds transversely through the o-ther side wall of the inter~
mediate transmission case 5. Parts of these rota-table rods 116a, 116b lyiny inside the case 5 have secured theretc cam members 117a, 117b to press the pair of braking members 104b, 104b ayainst the brake drum 4a, respectively. ~art of the lower rotatable rod 115b :Lying outside t.he case S has fixed thereto an oscil:latable arm 1:l~. The arln :L:L8 .i.s o~.)erati~ely connected to the brake operating lever 14 by way of the rod 24. Par-t of the uppe:r rotatabl.e rod 116a lying ou-tside the :L0 case 5 has fixed there-to an oscillatable arm 120 which is operatively connected to -the arm 118 -through a rod 121. The lever 1.4 is vertically oscillatably pivo-ted to a suppo.rt frcllrle 25 attached to -the intermedia-te transmission case 5. A
ratchet mechanism 26 comprising a ratche-t pawl 26a and a lock receiving member 26b is provided to lock -the lever 1~ at a desired position. The lever 14 has a press elemen-t 27 at an extreme end of its grip portion to cause oscillation of the ratche-t pawl 26a.
According to the above construc-tion, when the lcver 14 is pulled upward, the cam members 117a, 117b cause brakiny members 104b, 104b to con-tact the brake drum 4a -to provide braking, and when the lever 14 is oscilla-ted downward the braking is released.
The hrake means adapted -to apply a braking action to the drive pinion shaft by pressing a pair of braking melrlbers against the outer periphery oE a bra]ce drum as described above has an advantage over an internally acting brake mechan-ism wherein cam operating sha:Ets for actuating braking members extend forwardly or rearwardly of -the brake drum, in that the former may be fit-ted compactly withou-t requiring a large longitudinal space.
Claims (6)
EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS
FOLLOWS:
1. A tractor transmission comprising:
a front transmission case connected to a clutch housing and containing a main change speed mechanism;
a rear transmission case containing a differential mechanism and an auxiliary change speed mechanism;
an intermediate transmission disposed between and coupling said front transmission case and said rear transmission case;
a first travelling system transmission shaft mounted in said front transmission case;
a second travelling system transmission shaft mounted in said rear transmission case;
coupling means coupling the two travelling system transmission shafts;
a first power takeoff system transmission shaft mounted in said front transmission case;
a second power takeoff system transmission shaft mounted in said rear transmission case;
coupling means coupling the two power takeoff system transmission shafts;
a bevel pinion shaft of said differential mechanism mounted in said rear transmission case and having one end thereof protruding into said intermediate transmission case;
a brake drum secured to said one end of the bevel pinion shaft protruding into said intermediate transmission case; and brake means provided on said intermediate transmission case and adapted to press against said brake drum.
a front transmission case connected to a clutch housing and containing a main change speed mechanism;
a rear transmission case containing a differential mechanism and an auxiliary change speed mechanism;
an intermediate transmission disposed between and coupling said front transmission case and said rear transmission case;
a first travelling system transmission shaft mounted in said front transmission case;
a second travelling system transmission shaft mounted in said rear transmission case;
coupling means coupling the two travelling system transmission shafts;
a first power takeoff system transmission shaft mounted in said front transmission case;
a second power takeoff system transmission shaft mounted in said rear transmission case;
coupling means coupling the two power takeoff system transmission shafts;
a bevel pinion shaft of said differential mechanism mounted in said rear transmission case and having one end thereof protruding into said intermediate transmission case;
a brake drum secured to said one end of the bevel pinion shaft protruding into said intermediate transmission case; and brake means provided on said intermediate transmission case and adapted to press against said brake drum.
2. A tractor transmission as claimed in Claim 1 wherein said brake means includes at least a pair of braking members disposed peripherally of said brake drum.
3. A tractor transmission as claimed in Claim 2 wherein said brake means further includes a cam operator attached to an end of a cross rod protruding into said intermediate transmission case, and a cam member adapted to contact said cam operator to press said pair of braking members against said brake drum.
4. A tractor transmission as claimed in Claim 3 wherein said brake means further includes a C-shaped leaf spring, said pair of braking members being secured to said leaf spring, and said cam piece being adapted to contact a lower end of said leaf spring.
5. A tractor transmission as claimed in Claim 1 wherein said brake means includes at least a pair of braking members disposed peripherally of said brake drum and adapted to press against said brake drum, each of said braking members having an end pivoted to a side wall of said inter-mediate transmission case.
6. A tractor transmission as claimed in Claim 5 wherein said brake means further includes cam members attached to ends of two rotatable rods protruding into said intermediate transmission case and adapted to press said pair of braking members against said brake drum.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4864279A JPS55140630A (en) | 1979-04-19 | 1979-04-19 | Brake system for agricultural tractor |
| JP48642/1979 | 1979-04-19 | ||
| JP49546/1979 | 1979-04-20 | ||
| JP4954679A JPS6026744B2 (en) | 1979-04-20 | 1979-04-20 | Agricultural tractor braking device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1115991A true CA1115991A (en) | 1982-01-12 |
Family
ID=26388943
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA350,219A Expired CA1115991A (en) | 1979-04-19 | 1980-04-18 | Tractor transmission |
Country Status (2)
| Country | Link |
|---|---|
| CA (1) | CA1115991A (en) |
| DE (1) | DE3015029C2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1143965A (en) * | 1979-04-19 | 1983-04-05 | Tomeaki Tama | Tractor having a parking brake |
| IT1296876B1 (en) * | 1997-12-17 | 1999-08-02 | Piaggio Veicoli Europ | COMPACT VARIABLE STRUCTURE IN A MOTOR TRANSMISSION FOR MOTOR VEHICLES WITH ONE OR MORE DRIVE WHEELS |
| ITBO20030533A1 (en) | 2003-09-15 | 2005-03-16 | Cnh Italia Spa | PARKING BRAKE FOR A MOTOR VEHICLE, IN PARTICULAR FOR A TRACTOR |
| US11345267B2 (en) | 2020-03-06 | 2022-05-31 | Howe & Howe Inc. | Delivering fluid through a vehicle |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3729074A (en) * | 1971-06-14 | 1973-04-24 | Caterpillar Tractor Co | Parking brake control with transmission interlock |
| JPS5536135A (en) * | 1978-08-31 | 1980-03-13 | Kubota Ltd | Agricultural tractor |
-
1980
- 1980-04-18 DE DE19803015029 patent/DE3015029C2/en not_active Expired
- 1980-04-18 CA CA350,219A patent/CA1115991A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE3015029C2 (en) | 1985-06-27 |
| DE3015029A1 (en) | 1980-10-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |