Towbar coupling system

Description

[0001] The present invention relates to a drawbar coupling system and a vehicle comprising the drawbar coupling system.

[0002] Drawbar coupling systems typically comprise a pin which is configured to engage a drawbar to couple a trailer to a truck. These pins can usually be moved manually with a lever, but are ergonomically difficult to use.

[0003] It is known from EP 1 253 027 A1 to provide a device for opening trailer couplings.

[0004] It is known from DE 94 05 462 U1 to provide a device for disconnecting a trailer coupling.

[0005] According to a first aspect, there is provided a drawbar coupling system for coupling a drawbar to a vehicle, the drawbar coupling system comprising: a mount configured to fix the drawbar coupling system to a vehicle, and an actuation unit, the actuation unit comprising: a pin configured to move along a pin axis between a retracted position and an extended position; an engagement zone within which the pin is at least partially disposed in the extended position for engagement with a drawbar, wherein the pin is removed from the engagement zone when in the retracted position; a lever provided with a handle, the lever being configured to rotate through a travel between a first lever position and a second lever position, wherein the handle is closer to the mount in the first lever position than in the second lever position; and a transmission assembly configured to convert rotational movement of the lever from the first lever position to the second lever position into movement of the pin along the pin axis from the extended position to the retracted position.

[0006] The actuation unit of the drawbar coupling system may comprise a housing. The housing may be adjacent to the engagement zone, and may house the pin in the retracted position and / or partially house the pin in the extended position.

[0007] The transmission assembly comprises a first wheel fixed to the lever and a second wheel mechanically coupled to the pin. The first wheel is mechanically coupled to the second wheel throughout the travel of the lever to transfer opposing rotary motion from the first wheel to the second wheel.

[0008] The first wheel may have a first pitch diameter and the second wheel may have a second pitch diameter, and wherein the first pitch diameter may be equal to the second pitch diameter or smaller than the second pitch diameter.

[0009] The first wheel may be a first gear sector and the second wheel may be a second gear sector. The first gear sector may be configured to mesh with the second gear sector. The actuation unit may further comprise a stop at least partially disposed within an addendum circle of the first gear sector and configured to abut the first gear sector so as to limit the travel of the lever beyond the first lever position.

[0010] The transmission assembly further comprises a shaft which is mechanically coupled to the second wheel such that the pin is mechanically coupled to the second wheel via the shaft.

[0011] The shaft comprises a protrusion which is configured to be at least partially received within an internal recess of the second wheel such that the shaft and the second wheel are able to at least partially rotate relative to one another independently of one another. The transmission assembly is further configured so that when the lever is in the first position and the shaft is in a primary position corresponding to the pin being in the extended position, the shaft abuts a first end of the internal recess such that a rotation of the lever toward the second position drives the shaft towards a secondary position corresponding to the pin being in the retracted position. The transmission assembly is further configured so that when the lever is in the second position and the shaft is in the secondary position, the shaft and the second wheel are able to rotate independently such that the lever is able to be returned to the first position without the shaft being rotated towards the primary position. The transmission assembly is further configured so that when the lever is in the first position, the shaft and the second wheel are able to rotate independently such that the shaft is able to be rotated between the primary position and the secondary position without the lever being rotated between the first position and the second position.

[0012] The actuation unit may further comprise a biasing element configured to bias the pin to the extended position, and a holding mechanism configured to hold the pin in the retracted position when engaged so that the lever is able to return from the second position to the first position without moving the shaft or the pin. The holding mechanism may be configured to be selectively released so that the biasing element returns the pin to the extended position.

[0013] The transmission assembly may further comprise a lever biasing member configured to bias the lever toward the first lever position.

[0014] The actuation unit may further comprise an actuation assembly configured to drive the pin to move between the retracted position and the extended position; and a controller configured to control the actuation assembly based on a signal received from a user interface of the drawbar coupling system.

[0015] The actuation assembly may be configured to apply a force to the transmission assembly so as to drive the pin to move between the extended position and the retracted position.

[0016] The actuation assembly may be configured to apply a force to the shaft so as to drive the pin to move between the retracted position and the extended position.

[0017] The actuation assembly may comprise a pneumatic actuator.

[0018] The user interface may be a remote electronic device. The controller may be configured to receive the signal from the user interface via a wireless receiver.

[0019] According to a second aspect, there is provided a vehicle comprising the drawbar coupling system according to the first aspect.

[0020] Embodiments will now be described, by way of example only, with reference to the accompanying Figures, in which: Figure 1 schematically shows a vehicle comprising a drawbar coupling system; Figure 2 schematically shows a side view of an example drawbar coupling system; Figures 3a-3b schematically show a side view and a top cutaway view respectively of an actuation unit of the example drawbar coupling system of Figure 2; Figure 3c schematically shows a close-up cross-sectional view of the actuation unit of Figures 3a and 3b; and Figure 4 schematically shows a side sectional view of the drawbar coupling system of Figure 2 with a drawbar inserted into it.

[0021] Figure 1 shows a vehicle 10 comprising a drawbar coupling system 20. The drawbar coupling system 20 is fixed to a chassis 18 of the vehicle 10. The drawbar coupling system 20 is coupled to a drawbar 14 of a trailer 16, so that the drawbar 14 can pivot with respect to the chassis 18, through the drawbar coupling system 20, to permit pivoting movement of the trailer 16 with respect to the vehicle 10.

[0022] Figure 2 shows a side view of the drawbar coupling system 20 fixed to the vehicle 10. The drawbar coupling system 20 comprises an actuation unit 100, a funnel 22, and a mount 24. The mount 24 is configured to fix the drawbar coupling system 20 to the chassis 18 of the vehicle 10. The funnel 22 is configured to guide an end of a drawbar 14 into a centre of the funnel 22, corresponding with an engagement zone 26 of the actuation unit 100, so that the drawbar 14 can be securely coupled to the drawbar coupling system 20. In other words, the funnel 22 is configured to guide a drawbar 14 into the engagement zone 26, when the drawbar 14 is inserted into the drawbar coupling system 20. In some examples, the drawbar coupling system may not comprise a funnel.

[0023] Figure 3a shows a side view of the actuation unit 100 and Figure 3b shows a cutaway top view of the actuation unit 100. The actuation unit 100 comprises a housing 102 (which is shown as transparent in Figure 3a so that some internal components can be seen) and a lever 104 on the outside of the housing 102 provided with a handle 106. In this example, the housing 102 is adjacent to the engagement zone 26. Figures 3a and 3b show the lever 104 in a first lever position and Figure 2 shows the lever 104 in a second lever position. The lever 104 is configured to rotate through a travel between the first lever position and the second lever position. The handle 106 is closer to the mount 24 (not shown in Figures 3a and 3b) in the first lever position than in the second lever position.

[0024] The actuation unit 100 comprises a pin 110 configured to move along a pin axis 150 between a retracted position and an extended position. In the retracted position, the pin 110 is mostly disposed in the housing 102, and in the extended position, the pin 110 is protruding from the housing 102 so that it is at least partially disposed in the engagement zone 26. When in the extended position, the pin 110 can be engaged with a drawbar 14 to couple the drawbar 14 to the drawbar coupling system 20. The pin 110 is fully removed from the engagement zone 26 when in the retracted position to permit a drawbar 14 to be inserted into, or removed from, the engagement zone 26. Figure 3a shows the pin 110 in the extended position.

[0025] The actuation unit 100 comprises a transmission assembly 108 configured to convert rotational movement of the lever 104 from the first lever position to the second lever position into movement of the pin 110 along the pin axis 150 from the extended position to the retracted position. Having the lever 104 in this position allows a more ergonomic use of the drawbar coupling system 20, since in use, a user can pull the lever 104 towards themselves, and away from the mount 24 of the drawbar coupling system 20 to pull the pin 110 upwards into the retracted position, rather than the user being required to push the lever. In this example, the housing 102 also provides a surface on which a user can place a counteracting hand to help with pulling the lever 104.

[0026] In this example, the transmission assembly 108 comprises a first gear sector 112 and a second gear sector 114. The first gear sector 112 is fixed to the lever 104 and the second gear sector 114 is mechanically coupled to the pin 110. The first gear sector 112 meshes with the second gear sector 114 such that the first gear sector 112 is mechanically coupled to the second gear sector 114 throughout the travel of the lever 104, to transfer opposing rotary motion from the first gear sector 112 to the second gear sector 114.

[0027] In other examples, the transmission assembly may comprise a first wheel and a second wheel instead of the gear sectors. The first wheel and the second wheel may be mechanically coupled in any suitable way to transfer opposing rotary motion from the first wheel to the second wheel, such as by gear teeth, or by a pulley.

[0028] In this example, the first gear sector 112 has a first pitch diameter and the second gear sector 114 has a second pitch diameter. In this example, the first pitch diameter and the second pitch diameter have a ratio of 8:9. Therefore, the first pitch diameter is smaller than the second pitch diameter such as to provide a mechanical advantage when turning the lever 104, for ease of use. In other examples, the first pitch diameter may be equal to or larger than the second pitch diameter.

[0029] The transmission assembly 108 further comprises a shaft 122 which is mechanically coupled to the second gear sector 114. The shaft 122 is configured to be mechanically coupled to the pin 110 of the drawbar coupling system 20 via a hook 124 such that the second gear sector 114 is mechanically coupled to the pin 110 in the drawbar coupling system 20.

[0030] Figure 3c shows a close-up cross-sectional view of the transmission assembly 108 including the first gear sector 112, the second gear sector 114 and the shaft 122.

[0031] The shaft 122 comprises a protrusion 126 (also shown in Figure 3b), which is at least partially received within an internal recess 128 of the second gear sector 114. The protrusion 126 of the shaft 122 is configured to abut an inner surface of the internal recess 128 at respective ends. In between the ends of the internal recess 128, the protrusion 126 (and therefore the shaft 122) can rotate freely relative to the second gear sector 114. Therefore, the second gear sector 114 and the shaft 122 are configured to at least partially rotate relative to one another, independently of each other.

[0032] When the pin 110 is coupled to the shaft 122, the shaft 122 (and therefore the protrusion 126) is able to rotate between a primary position corresponding to the pin 110 being in the extended position (as shown in Figures 3a-3c) and a secondary position corresponding to the pin 110 being in the retracted position (e.g., in this example, in the secondary position, the protrusion 126 is rotated clockwise with respect to the primary position shown in Figure 3c until the protrusion 126 abuts the opposing inner surface of the internal recess 128).

[0033] When the lever 104 is in the first position (as shown in Figures 3b and 3c) and the shaft 122 is in the primary position (as shown in Figure 3c), the protrusion 126 abuts a first end of the internal recess 128 such that movement of the lever 104 from the first position to the second position (which moves the first gear sector 112 in an anticlockwise direction from that shown in Figure 3c), the second gear sector 114 is forced to rotate in a clockwise direction from that shown in Figure 3c which drives the shaft 122 to rotate to the secondary position such that the pin 110 is moved to the retracted position. Due to the internal recess 128, when the lever 104 is in the second position and the shaft 122 is in the secondary position, the shaft 122 and the second gear sector 114 are able to rotate independently of one another, so that on returning the lever 104 to the first position, the shaft 122 is not driven to return to the primary position by interaction of the protrusion 126 with the second gear sector 114, and therefore, absent any other external force, the shaft 122 remains in the secondary position such that the pin 110 remains in the retracted position. The shaft 122 can therefore be rotated between the primary position and the secondary position without the lever 104 being rotated between the first position and the second position.

[0034] In this example, the hook 124 is biased to a position corresponding to the extended position of the pin 110 by a biasing element 132. In this example, the biasing element 132 is in the form of a spring which is coupled to the hook 124, and pushes the hook 124, to push the pin 110 to the extended position. Therefore, in this example, when the shaft 122 is in the secondary position and the lever 104 returns to the first position, a holding force must provide a counteracting force against the biasing force of the biasing element 132 to hold the pin 110 in the retracted position. In this example, this is achieved with a holding mechanism 130 (shown in Figure 4) which is configured to hold the pin 110 in the retracted position once it is engaged by movement of the lever 104 to the second position, and so that the lever 104 is able to return to the first position from the second position without moving the shaft 122 or the pin 110. The holding mechanism 130 is configured to be selectively released so that the biasing element 132 returns the pin 110 to the extended position.

[0035] Figure 4 shows a cross-sectional view of the drawbar coupling system 20 with the pin 110 having been moved to the retracted position by the lever 104. In this example, the holding mechanism 130 comprises the hook 124 which is connected to the shaft 122, and a rod 140 on an end of the pin 110. The hook 124 is configured to rotate with the shaft 122, and engages with the rod 140 on a valley surface 138, to drive the pin 110 up from the extended position to the retracted position when the lever 104 is rotated to rotate the hook 124 in a clockwise direction to the position in which it is shown in Figure 4. The hook 124 is configured so that, at the retracted position, the rod 140 snaps into a seat 144 in the hook 124 so that the hook 124 cannot rotate back down, and therefore the pin 110 cannot return to the extended position. In the retracted position, a drawbar 14 can be inserted via the funnel 22 into the engagement zone 26.

[0036] It can be seen from Figure 4 that, in this example, in the retracted position, the pin 110 protrudes slightly out of the housing 102 of the actuation unit 100, so that, on entry to the engagement zone 26, the drawbar 14 abuts the pin 110 and pushes it further into the housing 102 from the retracted position. This small movement disengages the holding mechanism 130 (e.g., in this example, it pushes the rod 140 out of the seat 144 of the hook 124, thereby releasing the hook 124, and permits the pin 110 to return to the extended position by means of a second biasing element 154, which is configured to bias the pin 110 to the extended position, such that the rod 140 returns to the valley surface 138 of the hook 124.

[0037] Referring now to Figures 3a-3c, in this example, the transmission assembly 108 further comprises a lever biasing member 152 which is configured to bias the lever 104 towards the first lever position. Therefore, when the lever 104 is moved to the second lever position to move the pin 110 to the retracted position, the lever 104 will automatically return to the first lever position, and the pin 110 will remain in the retracted position until a drawbar 14 is inserted into the engagement zone 26, to disengage the holding mechanism 130.

[0038] In this example, the actuation unit 100 further comprises a stop 120 which is configured to limit the travel of the lever 104 beyond the first lever position (as shown in Figure 3a and 3c). In this example, the stop 120 is disposed within an addendum circle of the first gear sector 112 such that it abuts the first gear sector 112 when the lever 104 is in the first lever position. In other examples, the stop may be any suitable stop, or there may be no stop.

[0039] In this example, the actuation unit 100 further comprises an actuation assembly 200. The actuation assembly 200 is configured to drive the pin 110 to move between the retracted position and the extended position, independently of the lever 104. In this example, the actuation assembly 200 comprises a controller and a pneumatic actuator. The pneumatic actuator is configured to apply a force to the shaft 122 to drive the pin 110 to move between the extended position and the retracted position. The controller is configured to receive a signal from a user interface on a remote electronic device via a wireless receiver and to control the actuation assembly 200 based on the signal. In other examples, the user interface may not be remote, and may be connected to the controller with a wired connection.

[0040] In some examples the pneumatic actuator is configured to apply a force to any suitable part of the transmission assembly to move the pin. In other examples, the actuation assembly may comprise any suitable type of actuator, and the actuator may drive any suitable part of the drawbar coupling system to drive the pin between the extended position and the retracted position.

[0041] Use of a pneumatic actuator is advantageous because trucks which require drawbar coupling systems typically have a readily available supply of compressed air.

[0042] It will be understood that the invention is not limited to the embodiments above-described and various modifications and improvements can be made without departing from the concepts described herein. Except where mutually exclusive, any of the features may be employed separately or in combination with any other features and the disclosure extends to and includes all combinations and sub-combinations of one or more features described herein.

[0043] There is disclosed a drawbar coupling system for coupling a drawbar to a vehicle, the drawbar coupling system comprising: a mount configured to fix the drawbar coupling system to a vehicle, and an actuation unit, the actuation unit comprising: a pin configured to move along a pin axis between a retracted position and an extended position; an engagement zone within which the pin is at least partially disposed in the extended position for engagement with a drawbar, wherein the pin is removed from the engagement zone when in the retracted position; a lever provided with a handle, the lever being configured to rotate through a travel between a first lever position and a second lever position, wherein the handle is closer to the mount in the first lever position than in the second lever position; and a transmission assembly configured to convert rotational movement of the lever from the first lever position to the second lever position into movement of the pin along the pin axis from the extended position to the retracted position.

Claims

1. A drawbar coupling system (20) for coupling a drawbar to a vehicle, the drawbar coupling system comprising: a mount (24) configured to fix the drawbar coupling system to a vehicle, and an actuation unit (100), the actuation unit comprising: a pin (110) configured to move along a pin axis (150) between a retracted position and an extended position; an engagement zone (26) within which the pin is at least partially disposed in the extended position for engagement with a drawbar (14), wherein the pin is removed from the engagement zone when in the retracted position; a lever (104) provided with a handle (106), the lever being configured to rotate through a travel between a first lever position and a second lever position, wherein the handle is closer to the mount in the first lever position than in the second lever position; and a transmission assembly (108) configured to convert rotational movement of the lever from the first lever position to the second lever position into movement of the pin along the pin axis from the extended position to the retracted position, characterized in that the transmission assembly comprises: a first wheel fixed to the lever and a second wheel mechanically coupled to the pin, the first wheel being mechanically coupled to the second wheel throughout the travel of the lever to transfer opposing rotary motion from the first wheel to the second wheel; and a shaft (122) which is mechanically coupled to the second wheel such that the pin is mechanically coupled to the second wheel via the shaft, wherein the shaft comprises a protrusion (126) which is configured to be at least partially received within an internal recess (128) of the second wheel such that the shaft and the second wheel are able to at least partially rotate relative to one another independently of one another; and wherein the transmission assembly is further configured so that: when the lever is in the first position and the shaft is in a primary position corresponding to the pin being in the extended position, the shaft abuts a first end of the internal recess such that a rotation of the lever toward the second position drives the shaft towards a secondary position corresponding to the pin being in the retracted position; when the lever is in the second position and the shaft is in the secondary position, the shaft and the second wheel are able to rotate independently such that the lever is able to be returned to the first position without the shaft being rotated towards the primary position; and when the lever is in the first position, the shaft and the second wheel are able to rotate independently such that the shaft is able to be rotated between the primary position and the secondary position without the lever being rotated between the first position and the second position.

2. The drawbar coupling system according to claim 1, wherein the first wheel has a first pitch diameter and the second wheel has a second pitch diameter, and wherein the first pitch diameter is equal to the second pitch diameter or smaller than the second pitch diameter.

3. The drawbar coupling system according to claim 2, wherein the first wheel is a first gear sector (112) and the second wheel is a second gear sector (114), and wherein the first gear sector is configured to mesh with the second gear sector.

4. The drawbar coupling system according to claim 3, wherein the actuation unit further comprises a stop (120) at least partially disposed within an addendum circle of the first gear sector and configured to abut the first gear sector so as to limit the travel of the lever beyond the first lever position.

5. The drawbar coupling system according to any preceding claim, wherein the actuation unit further comprises: a biasing element (132) configured to bias the pin to the extended position, and a holding mechanism (130) configured to hold the pin in the retracted position when engaged so that the lever is able to return from the second position to the first position without moving the shaft or the pin, wherein the holding mechanism is configured to be selectively released so that the biasing element returns the pin to the extended position.

6. The drawbar coupling system according to any preceding claim, wherein the transmission assembly further comprises a lever biasing member (152) configured to bias the lever toward the first lever position.

7. The drawbar coupling system according to any preceding claim, the actuation unit further comprising: an actuation assembly (200) configured to drive the pin to move between the retracted position and the extended position; and a controller configured to control the actuation assembly based on a signal received from a user interface of the drawbar coupling system.

8. The drawbar coupling system according to claim 7, wherein the actuation assembly is configured to apply a force to the transmission assembly so as to drive the pin to move between the extended position and the retracted position.

9. The drawbar coupling system according to claim 7 or claim 8, wherein the actuation assembly is configured to apply a force to the shaft so as to drive the pin to move between the retracted position and the extended position.

10. The drawbar coupling system according to any of claims 7-9, wherein the actuation assembly comprises a pneumatic actuator.

11. The drawbar coupling system according to any of claims 7-10, wherein the user interface is a remote electronic device, and wherein the controller is configured to receive the signal from the user interface via a wireless receiver.

12. A vehicle (10) comprising the drawbar coupling system according to any preceding claim.