TECHNICAL FIELD

The present disclosure relates to a pedal switch according to the preamble of claim 1. Moreover, the present disclosure relates to a pedal arrangement according to the preamble of claim 10. Further, the present disclosure relates to a vehicle according to the preamble of claim 12.

BACKGROUND

Vehicles of today may be provided with a pedal that is adapted to assume positions in a first position range as well as a second position range. If the pedal is an acceleration pedal, the first position range may correspond to pedal positions with a relatively low fuel consumption of the vehicle whereas the second position range may correspond to pedal positions with larger fuel consumption. In order to avoid that an operator of the pedal, e.g. inadvertently or routinely, operates the pedal within the second position range, the pedal may be adapted to interact with a pedal switch that requires that the operators impart a relatively large force on the pedal in order to displace the pedal from a position in the first position range to a position in the second position range. An example of such a pedal switch is disclosed in US 2004/0163488 A1.

However, since the pedal needs to be imparted a relatively large force in order to reach a position within the second position range, there is a risk that the pedal is displaced to a greater extent than what was intended. In the example of an accelerator pedal, this may result in that an operator of the accelerator pedal obtains an acceleration that is larger than what was intended when the operator presses the pedal in order to enter the second position range.

SUMMARY

In view of the above, an object of the present invention is to provide a pedal switch that enables that a pedal may only be displaced from a position in a first position range to a position in a second position range by imparting the pedal a relatively large force but wherein the risk of obtaining an undesirably large displacement of the pedal, when entering the second position range, is appropriately low.

This object is achieved by a pedal switch according to claim 1.

As such, the present disclosure relates to a pedal switch for a pedal for a vehicle. The pedal switch comprises a first member adapted to be subjected to a force by the pedal, and a second member. Moreover, the pedal switch is adapted to assume a locking condition preventing relative displacement between the first and second member when the first member is subjected to a force by the pedal, which force is below a

predetermined threshold force.

Furthermore, the pedal switch is adapted to assume a non-locking condition allowing a relative displacement between the first and second members when the first member is subjected to a force by the pedal, which force is equal to or above the predetermined threshold force.

According to the present disclosure, the pedal switch comprises a damping arrangement adapted to dampen the relative displacement between the first and second members in the non-locking condition.

As used herein, the expression "damping arrangement" is intended to encompass any arrangement that is adapted to provide a resulting force in relation to the speed of the relative displacement, rather than the magnitude of the relative displacement as such, between two portions of the arrangement.

As used herein, the expression "pedal" is intended to mean any actuator that is arranged to be pressed and/or pulled by a user's foot and/or hand, or activated in any other way by a user. However, the pedal switch of the present disclosure is preferably used with a foot actuated pedal.

The pedal switch of the present disclosure implies that any large displacement of the pedal that could possibly occur when the pedal switch assumes its non-locking condition may be dampened by the damping arrangement of the pedal switch. As such, by virtue of the damping arrangement, the risk of obtaining an inadvertently large displacement of the pedal, when entering the second position range, may be reduced.

Moreover, once the pedal switch has assumed its non-locking condition, the damping arrangement preferably does not provide any significant counteracting force to the pedal, at least not if low or moderate forces are imparted on the pedal. As such, an operator of the pedal may operate the pedal within the second position range without having to use a large force for displacing the pedal. Optionally, the damping arrangement is adapted to dampen the relative displacement between the first and second members in the non-locking condition only, i.e. when the pedal is in the second position range only. The fact that the damping arrangement dampens the relative displacement in the non-locking condition only implies that an operator may operate the pedal within the first position range such that the pedal may be displaced at a relatively large displacement speed without the need of a large force imparted on the pedal.

Optionally, a first portion of the damping arrangement is adapted to engage with the first member and a second portion of the damping arrangement is adapted to engage with the second member.

Optionally, the pedal switch comprises a releasable locking arrangement being adapted to assume the locking condition and the non-locking condition. Optionally, the locking arrangement comprises a magnet, preferably a permanent magnet.

Optionally, the damping arrangement comprises a hydraulic dampener.

Optionally, the pedal switch comprises a biasing means, the biasing means being adapted to, in the non-locking condition, impart a force on the first member and/or the second member.

Optionally, the biasing means is adapted to impart a force on the first member and/or the second member such that the first member and/or the second member is/are displaced towards a position in which the pedal switch assumes the locking condition. Optionally, one of the first and second members comprises a housing and the other of the first and second members comprises a plunger extending at least partially within the housing.

Optionally, the damping arrangement is located at least partially within the housing.

A second aspect of the present disclosure relates to a pedal arrangement for a vehicle, the pedal arrangement comprising a pedal. The pedal arrangement further comprises a pedal switch according to the first aspect of the present disclosure.

Optionally, the pedal is an accelerator pedal.

A third aspect of the present disclosure relates to a vehicle comprising at least one pedal switch according to the first aspect of the present disclosure and/or a pedal arrangement according to the second aspect of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples.

In the drawings:

Fig. 1 illustrates a vehicle;

Fig. 2 illustrates an embodiment of a pedal assembly;

Fig. 3 illustrates an embodiment of a pedal switch according to the present invention, and Fig. 4 illustrates pedal force profile for an embodiment of a pedal assembly according to the present invention.

It should be noted that the appended drawings are not necessarily drawn to scale and that the dimensions of some features of the present invention may have been exaggerated for the sake of clarity. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The invention will, in the following, be exemplified by embodiments. It is to be understood, however, that the embodiments are included in order to explain principles of the invention and not to limit the scope of the invention defined by the appended claims.

The invention will below be described for a vehicle in the form of a wheel loader 10 such as the one illustrated in Fig. 1. The wheel loader 10 should be seen as an example of a vehicle which could comprise a pedal switch and/or a pedal arrangement according to the present invention. However, the pedal switch and/or pedal arrangement of the present invention may be implemented in a plurality of different types of vehicles. Purely by way of example, the pedal switch and/or pedal arrangement could be implemented in a truck, a lorry, a tractor, a car, a bus or any type of work machine. Fig. 2 schematically illustrates a pedal assembly 12 for a vehicle. The pedal assembly 12 comprises a pedal 14 which in Fig. 2 is implemented as an accelerator pedal. However, in other embodiments of the present invention, the pedal 14 may be of another type. Purely by way of example, the pedal may be adapted to actuate a machine (not shown) or another component (not shown) of the vehicle.

The pedal 14 is adapted to assume an initial position that is indicated by the dashed- dotted line 16 in Fig. 2. In embodiments of the present invention wherein the pedal 14 is an accelerator pedal, the initial position generally corresponds to an idling condition of the engine (not shown) actuated by the accelerator pedal 14.

The pedal 14 may be adapted to assume a plurality of positions, in a step-wise and/or continuous manner, within a first position range A as well as within a second position range B. The first position range A generally includes, or at least has one position that is adjacent to, the initial position 16 of the pedal 14. Each one of the positions of the second position range B preferably is located at a distance from the initial position of the pedal 14. As such, at least one position within the first position range A is generally located between the initial position 14 and the second position range B.

Moreover, the second position range B preferably includes the maximum position, i.e. the position corresponding to the largest possible displacement of the pedal 14. The first position range A generally corresponds to positions of the pedal 14 which relate to more environmentally friendly and/or more economic operating conditions of the device actuated by the pedal 14 than positions within the second position range B. In the example where the pedal 14 is an acceleration pedal, the first position range A may for instance correspond to positions of the accelerator pedal 14 which result in a fuel consumption below a certain threshold value.

Purely by way of example, the first position range A may be 2 to 5 times greater, preferably 3 to 4 times greater, than the second position range B.

The implementation of the pedal 14 illustrated in Fig. 2 is adapted to be pivoted around a pivot point 8 to thereby assume the above discussed plurality of positions. However, other implementations of the pedal 14 may be adapted to be subjected to a translation along a rectilinear or curved line (not shown in Fig. 2).

Moreover, the pedal arrangement 12 preferably comprises a pedal position control means 19, or a position controller. Preferably, the pedal position control means 19 comprises a pedal biasing means 21 , or pedal biasing arrangement, adapted to bias the pedal 4 in a direction towards the initial position 16 of the pedal 14. The pedal biasing means 21 is in Fig. 2 implemented as a torsion spring, but other implementations of the pedal biasing means 21 are of course possible. Moreover, the pedal position control means 19 may also comprise a pedal damping means (not shown), or pedal damping arrangement, adapted to dampen the motions of the pedal 14.

Fig. 2 further illustrates that the pedal assembly comprises a pedal switch 20. The pedal switch 20 is adapted to interact with the pedal 14 at least when the position of the pedal 14 enters, or is within, the second position range B. As may be gleaned from Fig. 2, the pedal switch 20 comprises a first member 22 adapted to be subjected to a force by the pedal 14, and a second member 24. The second member 24 may preferably be adapted to, at least under certain operating conditions, be in contact with a portion of the vehicle which portion is not fixedly attached to the pedal 14. Purely by way of example, the second member 24 may be adapted to abut a portion of the vehicle, such a pedal assembly base 26 that in turn is adapted to be mounted on an inner floor (not shown) of the vehicle.

The pedal switch 20 illustrated in Fig. 2 is adapted to be fixedly attached to the pedal 14 such that the pedal switch 20 only contacts the other portion of the vehicle when the pedal 14 assumes a position within the second position range B or when the pedal 14 enters the second position range B. However, in other embodiments of the present invention, the pedal switch 20 may be adapted to be attached to the other portion of the vehicle such that the pedal 14 contacts the pedal switch 20 only when the pedal 14 assumes a position within the second position range B or when the pedal 14 enters the second position range B.

Fig. 3 illustrates a preferred embodiment of the Fig. 2 pedal switch 20. As may be gleaned from Fig. 3, the first member 22 comprises a housing 23 and the second member 24 comprises a plunger 25.

Moreover, the pedal switch 20 illustrated in Fig. 3 comprises a releasable locking arrangement 26 adapted to assume the above discussed locking and non-locking conditions. The releasable locking arrangement 26 is in the Fig. 3 embodiment implemented as a magnet member 28, i.e. a member that comprises a permanent and/or an electric magnet, and a connection member 30. The connection member 30 preferably comprises a magnetic material.

The magnet 28 is fixedly attached to one of the first and second members 22, 24 and the connection member 30 is connected to the other one of the first and second members 22, 24. Optionally, the magnet 28 may form a unitary component with one of the first and second members 22, 24. Moreover, as a further option, the connection member 30 may form a unitary component with the other of the first and second members 22, 24. The connection member 30 may preferably comprise a plate of magnetic material. Purely by way of example, the magnetic material may be a steel alloy.

In the Fig. 3 embodiment, the magnet 28 is fixedly attached to a portion of the second member 24, i.e. the plunger 25 in Fig. 3, whereas the member of a magnetic material 30 is fixedly attached to a portion of the first member 22, i.e. the housing 23 in Fig. 3. However, in other embodiments of the pedal switch 20, the magnet 28 may instead be fixedly attached to the first member (this option is not shown in Fig. 3).

Instead of, or in addition to, the above discussed magnet 28 and connection member 30, other implementations of the releasable locking arrangement 26 may comprise other types of releasable locking means, or releasable locking arrangements. Purely by way of example, implementations of releasable locking arrangement 26 may include a snap-on connection (not shown in Fig. 3). As another non-limiting example, the locking arrangement 26 may be implemented as an arrangement that includes a load sensor (not shown) that is directly or indirectly connected to a locking actuator (not shown). The locking actuator may be adapted to prevent relative displacement between the first and second members 22, 24 when the load sensor is indicative of that the load imparted on the first member 22 is below a predetermined threshold value and to allow relative displacement when the load is above the threshold value.

Fig. 3 further illustrates that the pedal switch 20 comprises a damping arrangement 32 adapted to dampen the relative displacement between the first 22 and second members 24 in the non-locking condition. Preferably, the damping arrangement 32 is adapted to dampen the relative displacement between the first and second members 22, 24 only in the non-locking condition. Preferably, the damping arrangement 32 is separate from, i.e. distinct from, the pedal control means (which is indicated by reference number 19 in Fig. 2)·

The implementation of the damping arrangement 32 illustrated in Fig. 3 is a hydraulic dampener comprising a piston rod 34 and a cylinder 36 wherein the piston rod 34 is allowed to be displaced in relation to the cylinder 36. The cylinder 36 may preferably comprise a fluid such a liquid (e.g. oil) and/or a gas (e.g. air). However, other implementations of the damping arrangement 32 may for instance comprise an electronically controlled actuator (not shown) that is connected to an electronic control unit (not shown) that determines a resulting force of the actuator based on the speed of the relative displacement between e.g. the first and second members 22, 24.

Preferably, a first portion, e.g. the cylinder 36, of the damping arrangement 32 is adapted to engage with the first member 22 and a second portion, e.g. the piston rod 34, of the damping arrangement 32 is adapted to engage with the second member 24. In the embodiment of the pedal switch 20 illustrated in Fig. 3, the piston rod 34 is connected to the second member 24 and the cylinder 36 is connected to the first member 22. Purely by way of example, the cylinder 36 may be connected to a lid 39 that is fixedly or releasably attached to the housing 23 of the first member 22. As a non-limiting example, a portion of the pedal 14 may in embodiments of the pedal switch 20 constitute the lid 39 attached to the housing 23.

In the embodiment illustrated in Fig. 3, the damping arrangement 32 is located at least partially within the housing 23. Moreover, in the Fig. 3 embodiment, the damping arrangement 32 is located within a space that is at least partially delimited by the first member 22 and the second member 24. The fact that the damping arrangement 32 is located at least partially within the above space implies a reduced risk that the damping arrangement 32 is exposed to e.g. dirt or moisture.

In other embodiments of the pedal switch, the order may be reversed such that the piston rod 34 is connected to the first member 22 and the cylinder 36 is connected to the second member 24. Moreover, in further embodiments of the pedal switch 20, the damping arrangement 32 may be connected to only one of the first and second members 22, 24 and a portion of the damping arrangement 32 may be adapted to abut the other one of the first and second members 22, 24 when the pedal switch is in an un-locked condition.

Fig. 3 further illustrates that the pedal switch 20 may comprise a biasing means 38, or biasing member, which in Fig. 3 is implemented as a helical spring circumventing the cylinder 36. The biasing means 38 is adapted to, in said non-locking condition, impart a force on the first member 22 and/or the second member 24. Preferably, the stiffness of the biasing means 38 is relatively low. Purely by way of example, the stiffness of the biasing means 38 may be less than 25%, more preferred less than 15%, of the stiffness of the pedal biasing means 21.

Preferably, the biasing means 38 is adapted to impart a force on the first member 22 and/or the second member 24 such that the first member 22 and/or the second member 24 are displaced towards a position in which the pedal switch 20 assumes the locking condition. Fig. 4 illustrates a pedal force profile 40 for a pedal assembly 12 comprising a pedal switch 20 according to the present invention.

In the Fig. 4 diagram, the abscissa relates to the relative position of the pedal 14 and the ordinate relates to the force imparted on the pedal 14. As has been intimated hereinabove, the relative position of the pedal 14 may, depending on the implementation of the pedal 14, for instance relate to the angular or linear position of the pedal 14.

Fig. 4 further indicates the first position range A and the second position range B of the pedal 14. As may be gleaned from Fig. 4, when the pedal position is within the first position range A, the force required in order to obtain a position change of the pedal 14 is relatively low and the slope of the pedal force profile 40 in the first position range A generally corresponds to the stiffness of the pedal biasing means 21. However, in order to change the position of the pedal 14 from a position within the first position range A to a position within the second position range B, a force has to be imparted to the pedal 14 which, in addition to the force required in order to overcome the resulting force of the pedal biasing means 21 , exceeds the force required for the pedal switch 20 to assume its non-locking condition. Purely by way of example, the force required for the pedal switch 20 to assume its non-locking condition may be within the range of 20 - 70 N, preferably within the range of 30 - 60 N, more preferred within the range of 40 - 50 N. The force required for the pedal switch 20 to assume its non-locking condition is indicated by force range 42 in Fig. 4. The position 44 of the pedal 14 at which the pedal switch 20 engages with the pedal 14 depends inter alia on the size and position of the pedal switch 20 relative to the pedal 14.

When the above force has been imparted the pedal 14, the pedal switch 20 assumes its non-locking condition. When the non-locking condition is assumed, the force required to further displace the pedal 14 is substantially lower than the force needed to obtain the non-locking condition. Purely by way of example, the force required to further displace the pedal 14 may be less than 30%, preferably less than 15% of the force required to obtain the non-locking condition. As such, without the presence of any displacement controlling means of the pedal switch 20, there would be a risk that the pedal 14, after the non- locking condition had been assumed, would be imparted an undesirably large displacement.

However, by virtue of the pedal switch 20 of the present invention, the damping arrangement 38 will reduce the further displacement of the pedal 1 pedal switch 20 in the non-locking condition. As such, when the pedal switch 20 assumes its non-locking condition, the load imparted on the pedal 14 may be larger than what is actually needed in order to further displace the pedal 14. Thus, a relative displacement may be obtained between the first and second members 22, 24 the speed of which may be relatively large. The relative displacement results in that the damping arrangement 38 provides a damping force, the size of which is dependent on the speed of the relative displacement, which damping force counteracts the force imparted on the pedal 14. This counteracting force will reduce the displacement of the pedal 14. Fig. 4 illustrates three possible shapes 40', 40", 40"' of the pedal force profile 40 after the profile switch 20 has assumed its non-locking condition. The actual shape obtained depends inter alia on the amount of the force applied to the pedal 14 in the non-locking condition. The relative displacement between the first and second members 22, 24 is dampened, as is indicated by point 46 in Fig. 4, until the speed of the relative displacement between the members 22, 24 is close to zero.

If the position of the pedal 14 subsequently is to be changed from point 46 on the pedal force profile 40, the force needed to displace the pedal 14 substantially corresponds to the force required to overcome the pedal position control means 19 and possibly also the biasing means 38 of the pedal switch 20, should the pedal switch 20 comprise such a biasing means 38.

As such, an operator of the pedal 14 may operate the pedal 14 within the second position range B without having to impart a large force on the pedal 14.

It is to be understood that the present invention is not limited to the embodiments described above and illustrated in the drawings. As such, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims. For example, a single pedal switch according to the present invention may be connected to a plurality of pedals. As another example, a single pedal may comprise a plurality of pedal switches arranged to assume a locking condition at different predetermined thresholds.