CA1335421C - Speed and direction control system for tractor hydrostatic transmission - Google Patents
Speed and direction control system for tractor hydrostatic transmissionInfo
- Publication number
- CA1335421C CA1335421C CA000616710A CA616710A CA1335421C CA 1335421 C CA1335421 C CA 1335421C CA 000616710 A CA000616710 A CA 000616710A CA 616710 A CA616710 A CA 616710A CA 1335421 C CA1335421 C CA 1335421C
- Authority
- CA
- Canada
- Prior art keywords
- roller
- control
- transmission
- arm
- neutral position
- 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 - Fee Related
Links
Landscapes
- Steering Controls (AREA)
- Arrangement Or Mounting Of Control Devices For Change-Speed Gearing (AREA)
- Steering-Linkage Mechanisms And Four-Wheel Steering (AREA)
- Cooling, Air Intake And Gas Exhaust, And Fuel Tank Arrangements In Propulsion Units (AREA)
- Seats For Vehicles (AREA)
- Control Of Fluid Gearings (AREA)
Abstract
A control shaft is coupled for oscillating a pump swash plate of a reversible hydrostatic transmission in opposite directions from a neutral position and linked to a control arm that is fixed to the control shaft is a manual control lever that is moveable to opposite sides of a neutral position to respectively effect different forward and reverse transmission driving speeds. The control arm includes a roller at one end which is received within a specially shaped opening provided in a cam plate that is linked to the brake pedal of the tractor such that a cam surface of the cam plate opening acts on the control arm roller to simultaneously return the transmission swash plate and control lever to their respective neutral positions. A neutralizing assist includes a roller-carrying arm that is biased into contact with an elongate cam surface carried by a projection of the control arm and being formed arcuately about the axis of the control shaft. The cam surface has a V-notch formed intermediate of its opposite ends and a spring acts to keep the roller of the roller-carrying arm in contact with the cam surface. The V-notch is located such that the roller will move thereinto to force the control arm to move to its neutral position to precisely locate the transmission in its neutral position when the control lever is in its neutral position.
Description
HYDRO8TATIC TRaN8MI88ION
Related Ap~lication This is a divisional of Canadian application Serial Number 604,977 filed on 06 July 1989.
Background of the Invention The present invention relates to tractors equipped with hydrostatic transmissions and more specifically relates to speed and direction control systems for such transmissions.
Lawn and garden tractors are often equipped with a variable speed hydrostatic transmission including a pump embodying a swash plate that is pivotable, by a speed and direction control lever, to opposite sides of a centered, neutral, zero-displacement position to respective forward and reverse drive positions. It is known to interlock traction drive brake controls with the direction and speed controls of the hydrostatic transmission so that upon the brakes being applied, the control lever is moved to a centered neutral position corresponding to that of the swash plate. However, the structure for interlocking the brake and transmission controls suffer from one or more of the drawbacks of being too complex or of requiring frequent adjustment in order to ensure that the swash plate is in neutral when the control lever is in neutral.
Summary of the Invention According to the present invention, there is provided improved controls for tractor hydrostatic transmissions and, more specifically, there is provided an improved structure for ensuring that the swash plate of the transmission is in a neutral position when the transmission control lever is in its neutral position.
An object of the invention is to provide a control system for a hydrostatic transmission which reliably acts to simultaneously place the transmission control lever and swash plate in their respective neutral positions.
A further object of the invention is to provide a hydrostatic transmission control system, as described above, : i wherein easy adjustments may be made to ensure that the transmission control lever and swash plate move to their respective neutral positions at the same time.
These and other objects of the invention will become apparent from a reading of the ensuing description together with the appended drawings.
Brief Description of the Drawings FI~. 1 is a right front perspective view of a lawn and garden tractor embodying a hydrostatic transmission control system constructed in accordance with the principles of the present invention.
FIG. 2 is a left rear perspective view showing a portion of the hydrostatic transmission control system.
FIG. 3 is a right side elevational view of a portion of the control system shown in FIG. 2.
FIG. 4 is a left rear perspective view showing a linkage interlocking the tractor brake system with the transmission control system shown in FIG. 2.
Description of the Preferred Embodiment Referring now to FIG. 1, therein is shown a work vehicle in the form of a lawn and garden tractor 20 including a longitudinally extending main frame 22 supported on a front pair of steerable wheels 30 and 32 and a rear pair of drive wheels 46 and 48. An engine (not shown) is supported on a forward portion of the frame 22 in a compartment defined in part by a hood 50.
Mounted to the frame 22 rearwardly of the hood 50 is a combined operator platform and fender deck structure 68. A
seat assembly 76 is mounted to the structure 68 so as to position an operator within easy reach of a steering wheel 38 located forwardly of the seat and of an upright, transmission control lever 66 projecting through the right hand fender and forming a part of a transmission direction and speed control system 70 (FIG. 2) provided for controlling the output speed and direction of a hydrostatic transmission.
Referring now to FIGS. 2-4, the details of the transmission control system 70 will be described in detail.
1 335`42 1 ~ Specifically, the control system 70 includes an oscillatable transverse transmission control shaft 360 which is connected, in a conventional manner not shown, to effect movement of the transmission pump swash plate in increasing amounts to opposite sides of a centered neutral position to thereby effect increasing forward and reverse driving speeds. A
transmission control arm 358 includes a block-like mounting portion 366, clamped to the shaft 360, and upper, forward and rearward extensions 430, 400 and 380, respectively, formed integrally with the mounting portion 366. The rearward extension 380 terminates in a curved portion 368 having a rearwardly facing cam surface 370 disposed arcuately about the axis of the control shaft 360 and in which a V-notch 384 is formed so as to divide the surface into upper and lower surface portions 372 and 374, respectively, with the surface portion 372 being the longer of the two to accommodate a wider range of forward than rearward operating speeds as will be apparent from the description below.
A first control input to the control arm 358 is received at the upper extension 430 and is provided by the transmission control lever 66, the latter being coupled by a U-shaped member 352, to a rotatably mounted cross shaft 354 which in turn includes a depending arm 361 that is interconnected with the upper extension 430 by a connecting rod 362. The connecting rod 362 is made to be adjustable in length, for a purpose explained below, by the provision of a universal connector 434 threaded onto the forward end of the rod 362 and held in place by a jam nut 438.
A second control input to the control arm 358 is received at the forward extension 400 and is provided by a brake pedal 72 having its lower end fixed to an outboard end of a cross shaft 150 rotatably mounted in the frame members 24 and 26. A
brake control shaft 408 is rotatably mounted in the frame members at a location rearwardly of the shaft 150 and adjacent the forward extension 400 of the control arm 358. A motion transfer link 418 is coupled between an upper end of an arm fixed to and projecting upwardly from the shaft 150 and a - lower end of an arm fixed to and depending from the shaft 408.
A cam plate 402 is fixed to the shaft 408 and is provided with an opening 410 defining a cam surface 414. A cam follower in the form of a roller 412 (FIG. 3) is received on a cylindrical pin 404 (FIG. 2) which is eccentrically pivotally mounted to the forward extension 400 of the control arm 358, the roller being disposed within the cam plate opening 410 for engagement by the cam surface 414 when the brake pedal 72 is depressed, the shape of the cam surface being such as to return the control arm 358 to its neutral position so as to neutralize the transmission. Of course, the transmission control lever 66 will also be returned to neutral. However, the shape of the cam plate opening 410 is such that with the brake pedal 72 released, the roller 412 will move freely within the opening when the lever 66 is shifted fore-and-aft from its neutral position to effect forward and reverse driving conditions in the transmission.
A neutralizing assist 379 is associated with the curved portion 370 of the control arm 358 so as to ensure that the control arm is precisely placed in neutral whenever the control lever 66 is placed in its neutral position or when the brake pedal 72 is depressed. Specifically, the assist 379 includes a roller support arm 388 having its lower end pivotally received on a cylindrical pin 392 that is selectively pivotable about and held in place by a cap screw 396 that passes eccentrically through the pin 392. The cylindrical pin 392 is mounted adjacent the control arm curved portion 368 and a roller 390 is mounted to the upper end of the arm 388 and held into engagement with the cam surface 370 by a coil tension spring 440 having hooks formed on its opposite ends and respectively secured in place by the fasteners holding the rollers 390 and 412 in place. When the control lever 66 is in or near a full forward speed position, the transmission control arm 358, as viewed from the left in FIG. 2, will be in or near a full clockwise position and the roller 390 will be engaged with an upper end of the upper cam surface portion 372. As the control lever 66 is moved back - towards its neutral position, the arm 358 will pivot counterclockwise and the surface portion 372 will travel upwardly relative to the roller 390 and the V-notch 384 will approach the roller 390. The shape of the V-notch 384 is designed such that when the roller 390 is just about to enter the notch, the transmission will be slowed to the extent that the vehicle will now be traveling forwardly at about 1/2 mph.
This is the minimum operating speed of the vehicle since the action of the spring 440 will immediately neutralize the arm 358 once the roller 390 moves over the edge of the notch.
When the control lever 66 is in or near a full rearward speed position, the control arm will be at or near its full counterclockwise position and the roller 390 will be engaged with a lower end of the lower surface portion 374. As the control lever is moved back towards its neutral position, the arm 358 will pivot clockwise and the surface portion 374 will travel downwardly relative to the roller 390 and the notch 384 will approach the roller 390. Again, because of the shape of the notch 384, the vehicle travel speed will be about 1/2 mph in reverse when the roller 390 is just about to enter the notch with the action of the spring 440 acting to immediately neutralize the arm 358 once the roller moves over the edge of the notch.
The eccentric mountings of the cylindrical pins 392 and 404 allow for quick, easy and accurate adjustment of the positions of the rollers 390 and 412 so that when the control arm 358 is positioned in its neutral position corresponding to the neutral position of the hydrostatic transmission the roller 390 will be centered in the V-notch 384 and when the brake pedal 72 is depressed, the roller 412 will cooperate with the cam surface 414 to return the arm 358 to its neutral position from any other position. Of course, the length of the connecting link 362 can be adjusted to ensure that the control arm 358 is in neutral when the control lever 66 is in neutral.
Related Ap~lication This is a divisional of Canadian application Serial Number 604,977 filed on 06 July 1989.
Background of the Invention The present invention relates to tractors equipped with hydrostatic transmissions and more specifically relates to speed and direction control systems for such transmissions.
Lawn and garden tractors are often equipped with a variable speed hydrostatic transmission including a pump embodying a swash plate that is pivotable, by a speed and direction control lever, to opposite sides of a centered, neutral, zero-displacement position to respective forward and reverse drive positions. It is known to interlock traction drive brake controls with the direction and speed controls of the hydrostatic transmission so that upon the brakes being applied, the control lever is moved to a centered neutral position corresponding to that of the swash plate. However, the structure for interlocking the brake and transmission controls suffer from one or more of the drawbacks of being too complex or of requiring frequent adjustment in order to ensure that the swash plate is in neutral when the control lever is in neutral.
Summary of the Invention According to the present invention, there is provided improved controls for tractor hydrostatic transmissions and, more specifically, there is provided an improved structure for ensuring that the swash plate of the transmission is in a neutral position when the transmission control lever is in its neutral position.
An object of the invention is to provide a control system for a hydrostatic transmission which reliably acts to simultaneously place the transmission control lever and swash plate in their respective neutral positions.
A further object of the invention is to provide a hydrostatic transmission control system, as described above, : i wherein easy adjustments may be made to ensure that the transmission control lever and swash plate move to their respective neutral positions at the same time.
These and other objects of the invention will become apparent from a reading of the ensuing description together with the appended drawings.
Brief Description of the Drawings FI~. 1 is a right front perspective view of a lawn and garden tractor embodying a hydrostatic transmission control system constructed in accordance with the principles of the present invention.
FIG. 2 is a left rear perspective view showing a portion of the hydrostatic transmission control system.
FIG. 3 is a right side elevational view of a portion of the control system shown in FIG. 2.
FIG. 4 is a left rear perspective view showing a linkage interlocking the tractor brake system with the transmission control system shown in FIG. 2.
Description of the Preferred Embodiment Referring now to FIG. 1, therein is shown a work vehicle in the form of a lawn and garden tractor 20 including a longitudinally extending main frame 22 supported on a front pair of steerable wheels 30 and 32 and a rear pair of drive wheels 46 and 48. An engine (not shown) is supported on a forward portion of the frame 22 in a compartment defined in part by a hood 50.
Mounted to the frame 22 rearwardly of the hood 50 is a combined operator platform and fender deck structure 68. A
seat assembly 76 is mounted to the structure 68 so as to position an operator within easy reach of a steering wheel 38 located forwardly of the seat and of an upright, transmission control lever 66 projecting through the right hand fender and forming a part of a transmission direction and speed control system 70 (FIG. 2) provided for controlling the output speed and direction of a hydrostatic transmission.
Referring now to FIGS. 2-4, the details of the transmission control system 70 will be described in detail.
1 335`42 1 ~ Specifically, the control system 70 includes an oscillatable transverse transmission control shaft 360 which is connected, in a conventional manner not shown, to effect movement of the transmission pump swash plate in increasing amounts to opposite sides of a centered neutral position to thereby effect increasing forward and reverse driving speeds. A
transmission control arm 358 includes a block-like mounting portion 366, clamped to the shaft 360, and upper, forward and rearward extensions 430, 400 and 380, respectively, formed integrally with the mounting portion 366. The rearward extension 380 terminates in a curved portion 368 having a rearwardly facing cam surface 370 disposed arcuately about the axis of the control shaft 360 and in which a V-notch 384 is formed so as to divide the surface into upper and lower surface portions 372 and 374, respectively, with the surface portion 372 being the longer of the two to accommodate a wider range of forward than rearward operating speeds as will be apparent from the description below.
A first control input to the control arm 358 is received at the upper extension 430 and is provided by the transmission control lever 66, the latter being coupled by a U-shaped member 352, to a rotatably mounted cross shaft 354 which in turn includes a depending arm 361 that is interconnected with the upper extension 430 by a connecting rod 362. The connecting rod 362 is made to be adjustable in length, for a purpose explained below, by the provision of a universal connector 434 threaded onto the forward end of the rod 362 and held in place by a jam nut 438.
A second control input to the control arm 358 is received at the forward extension 400 and is provided by a brake pedal 72 having its lower end fixed to an outboard end of a cross shaft 150 rotatably mounted in the frame members 24 and 26. A
brake control shaft 408 is rotatably mounted in the frame members at a location rearwardly of the shaft 150 and adjacent the forward extension 400 of the control arm 358. A motion transfer link 418 is coupled between an upper end of an arm fixed to and projecting upwardly from the shaft 150 and a - lower end of an arm fixed to and depending from the shaft 408.
A cam plate 402 is fixed to the shaft 408 and is provided with an opening 410 defining a cam surface 414. A cam follower in the form of a roller 412 (FIG. 3) is received on a cylindrical pin 404 (FIG. 2) which is eccentrically pivotally mounted to the forward extension 400 of the control arm 358, the roller being disposed within the cam plate opening 410 for engagement by the cam surface 414 when the brake pedal 72 is depressed, the shape of the cam surface being such as to return the control arm 358 to its neutral position so as to neutralize the transmission. Of course, the transmission control lever 66 will also be returned to neutral. However, the shape of the cam plate opening 410 is such that with the brake pedal 72 released, the roller 412 will move freely within the opening when the lever 66 is shifted fore-and-aft from its neutral position to effect forward and reverse driving conditions in the transmission.
A neutralizing assist 379 is associated with the curved portion 370 of the control arm 358 so as to ensure that the control arm is precisely placed in neutral whenever the control lever 66 is placed in its neutral position or when the brake pedal 72 is depressed. Specifically, the assist 379 includes a roller support arm 388 having its lower end pivotally received on a cylindrical pin 392 that is selectively pivotable about and held in place by a cap screw 396 that passes eccentrically through the pin 392. The cylindrical pin 392 is mounted adjacent the control arm curved portion 368 and a roller 390 is mounted to the upper end of the arm 388 and held into engagement with the cam surface 370 by a coil tension spring 440 having hooks formed on its opposite ends and respectively secured in place by the fasteners holding the rollers 390 and 412 in place. When the control lever 66 is in or near a full forward speed position, the transmission control arm 358, as viewed from the left in FIG. 2, will be in or near a full clockwise position and the roller 390 will be engaged with an upper end of the upper cam surface portion 372. As the control lever 66 is moved back - towards its neutral position, the arm 358 will pivot counterclockwise and the surface portion 372 will travel upwardly relative to the roller 390 and the V-notch 384 will approach the roller 390. The shape of the V-notch 384 is designed such that when the roller 390 is just about to enter the notch, the transmission will be slowed to the extent that the vehicle will now be traveling forwardly at about 1/2 mph.
This is the minimum operating speed of the vehicle since the action of the spring 440 will immediately neutralize the arm 358 once the roller 390 moves over the edge of the notch.
When the control lever 66 is in or near a full rearward speed position, the control arm will be at or near its full counterclockwise position and the roller 390 will be engaged with a lower end of the lower surface portion 374. As the control lever is moved back towards its neutral position, the arm 358 will pivot clockwise and the surface portion 374 will travel downwardly relative to the roller 390 and the notch 384 will approach the roller 390. Again, because of the shape of the notch 384, the vehicle travel speed will be about 1/2 mph in reverse when the roller 390 is just about to enter the notch with the action of the spring 440 acting to immediately neutralize the arm 358 once the roller moves over the edge of the notch.
The eccentric mountings of the cylindrical pins 392 and 404 allow for quick, easy and accurate adjustment of the positions of the rollers 390 and 412 so that when the control arm 358 is positioned in its neutral position corresponding to the neutral position of the hydrostatic transmission the roller 390 will be centered in the V-notch 384 and when the brake pedal 72 is depressed, the roller 412 will cooperate with the cam surface 414 to return the arm 358 to its neutral position from any other position. Of course, the length of the connecting link 362 can be adjusted to ensure that the control arm 358 is in neutral when the control lever 66 is in neutral.
Claims (5)
1. In a tractor equipped with a reversible hydrostatic transmission coupled for driving a pair of drive wheels of the tractor, the transmission including a swash plate oscillatable in opposite first and second directions from a centered neutral position for respectively establishing increasing forward and reverse driving speeds of the tractor, and a control shaft coupled to the swash plate and oscillatable about a first axis so as to effect movement of said swash plate, an improved control for effecting oscillation of said control shaft comprising:
a control arm fixed to said control shaft and including a free end defined by an elongate cam surface formed arcuately about said axis and including a notch located between opposite ends of the cam surface;
a manual speed and direction control lever;
link means connecting said control lever to said control arm for effecting rocking movement of the latter for selectively effecting forward and reverse driving conditions in the transmission in response to movement of the control lever in opposite first and second directions from a neutral position; and a neutralizing assist for ensuring that the transmission will be placed in its neutral position when the control lever is placed in its neutral position, the assist including:
a roller support arm carrying a roller at one end and being pivotally mounted for swinging about a second axis extending parallel to the first axis and located in the vicinity of said cam surface with said roller being in contact with said cam surface;
biasing means acting on said roller support arm and urging said roller against said cam surface; and said roller and said notch being sized and shaped such that as said control arm approaches a centered position corresponding to the neutral position of the transmission the roller will enter the notch and move the control arm so as to effect neutralization of the transmission.
a control arm fixed to said control shaft and including a free end defined by an elongate cam surface formed arcuately about said axis and including a notch located between opposite ends of the cam surface;
a manual speed and direction control lever;
link means connecting said control lever to said control arm for effecting rocking movement of the latter for selectively effecting forward and reverse driving conditions in the transmission in response to movement of the control lever in opposite first and second directions from a neutral position; and a neutralizing assist for ensuring that the transmission will be placed in its neutral position when the control lever is placed in its neutral position, the assist including:
a roller support arm carrying a roller at one end and being pivotally mounted for swinging about a second axis extending parallel to the first axis and located in the vicinity of said cam surface with said roller being in contact with said cam surface;
biasing means acting on said roller support arm and urging said roller against said cam surface; and said roller and said notch being sized and shaped such that as said control arm approaches a centered position corresponding to the neutral position of the transmission the roller will enter the notch and move the control arm so as to effect neutralization of the transmission.
2. The tractor of claim 1 wherein said roller support arm is pivotally mounted by an eccentric structure permitting the effective length of the arm to be adjusted so as to adjust the roller relative to the cam surface for ensuring that the transmission is neutralized whenever the roller enters the notch.
3. The tractor of claim 1 wherein said notch and roller are shaped relative to each other so that the tractor transmission can operate the tractor at speeds as slow as 1/2 mph forwardly or in reverse without the roller entering the notch to neutralize the transmission.
4. The tractor of claim 1 and further including:
a brake pedal coupled to a brake control shaft pivotally mounted in the vicinity of and being parallel to said control shaft;
a cam plate fixed to said brake control shaft and containing an opening defining a cam surface;
said control arm having a projection extending in a direction opposite from the curved end of the arm;
a roller being mounted to said projection and disposed within said opening in the cam plate; and said roller and cam surface defined by the opening in said cam plate being so disposed and shaped that upon the brake pedal being moved in a direction for effecting braking operation, the cam surface will engage the roller and effect rocking movement of the control arm to neutralize the transmission, assuming it is not already neutralized, and at the same time return the control lever to its corresponding neutral position.
a brake pedal coupled to a brake control shaft pivotally mounted in the vicinity of and being parallel to said control shaft;
a cam plate fixed to said brake control shaft and containing an opening defining a cam surface;
said control arm having a projection extending in a direction opposite from the curved end of the arm;
a roller being mounted to said projection and disposed within said opening in the cam plate; and said roller and cam surface defined by the opening in said cam plate being so disposed and shaped that upon the brake pedal being moved in a direction for effecting braking operation, the cam surface will engage the roller and effect rocking movement of the control arm to neutralize the transmission, assuming it is not already neutralized, and at the same time return the control lever to its corresponding neutral position.
5. The tractor of claim 1 wherein said link means includes a length adjustable link whereby the control lever may be precisely adjusted to its neutral position to correspond to the position of the control shaft for effecting neutralization of the transmission.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US226,249 | 1988-07-29 | ||
| US07/226,249 US4969533A (en) | 1988-07-29 | 1988-07-29 | Work vehicle |
| CA000604977A CA1325888C (en) | 1988-07-29 | 1989-07-06 | Work vehicle |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000604977A Division CA1325888C (en) | 1988-07-29 | 1989-07-06 | Work vehicle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1335421C true CA1335421C (en) | 1995-05-02 |
Family
ID=25672863
Family Applications (6)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000616710A Expired - Fee Related CA1335421C (en) | 1988-07-29 | 1993-09-09 | Speed and direction control system for tractor hydrostatic transmission |
| CA000616714A Expired - Fee Related CA1336105C (en) | 1988-07-29 | 1993-09-09 | Tractor operator presence indicator switch mounting |
| CA000616712A Expired - Fee Related CA1335422C (en) | 1988-07-29 | 1993-09-09 | Hydrostatic transmission bypass valve assembly |
| CA000616715A Expired - Fee Related CA1334368C (en) | 1988-07-29 | 1993-09-09 | Steering effort and responsiveness adjustment |
| CA000616711A Expired - Fee Related CA1334816C (en) | 1988-07-29 | 1993-09-09 | Cooling and combustion air filtering system for a tractor |
| CA000616713A Expired - Fee Related CA1334369C (en) | 1988-07-29 | 1993-09-09 | Steering wheel tilt mechanism |
Family Applications After (5)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000616714A Expired - Fee Related CA1336105C (en) | 1988-07-29 | 1993-09-09 | Tractor operator presence indicator switch mounting |
| CA000616712A Expired - Fee Related CA1335422C (en) | 1988-07-29 | 1993-09-09 | Hydrostatic transmission bypass valve assembly |
| CA000616715A Expired - Fee Related CA1334368C (en) | 1988-07-29 | 1993-09-09 | Steering effort and responsiveness adjustment |
| CA000616711A Expired - Fee Related CA1334816C (en) | 1988-07-29 | 1993-09-09 | Cooling and combustion air filtering system for a tractor |
| CA000616713A Expired - Fee Related CA1334369C (en) | 1988-07-29 | 1993-09-09 | Steering wheel tilt mechanism |
Country Status (1)
| Country | Link |
|---|---|
| CA (6) | CA1335421C (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1392080B1 (en) * | 2008-12-05 | 2012-02-09 | Ggp Italy Spa | SAFETY DEVICE CONNECTED TO THE PRESENCE OF THE OPERATOR ON THE SEAT OF A TRACTOR |
-
1993
- 1993-09-09 CA CA000616710A patent/CA1335421C/en not_active Expired - Fee Related
- 1993-09-09 CA CA000616714A patent/CA1336105C/en not_active Expired - Fee Related
- 1993-09-09 CA CA000616712A patent/CA1335422C/en not_active Expired - Fee Related
- 1993-09-09 CA CA000616715A patent/CA1334368C/en not_active Expired - Fee Related
- 1993-09-09 CA CA000616711A patent/CA1334816C/en not_active Expired - Fee Related
- 1993-09-09 CA CA000616713A patent/CA1334369C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA1334368C (en) | 1995-02-14 |
| CA1336105C (en) | 1995-06-27 |
| CA1335422C (en) | 1995-05-02 |
| CA1334816C (en) | 1995-03-21 |
| CA1334369C (en) | 1995-02-14 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |