GB2578585A

GB2578585A - Mower with switch

Info

Publication number: GB2578585A
Application number: GB1817751.9A
Authority: GB
Inventors: John Gittins
Original assignee: Allett Ltd
Current assignee: Allett Ltd
Priority date: 2018-10-31
Filing date: 2018-10-31
Publication date: 2020-05-20
Anticipated expiration: 2038-10-31
Also published as: GB201817751D0; GB2578585B

Abstract

A mower 200 has a motor 110 for driving the mower 200 at a drive speed, a controller 130 for controlling a speed of the motor 110, and a switch 140 mounted on a handle 240 or handlebar of the mower 200. The switch 140 is configured to signal the controller 130 to alter the drive speed of the mower 200 between a normal drive speed and at least one pre-set drive speed.

Description

MOWER WITH SWITCH

FIELD OF INVENTION

The present invention relates to a mower having a switch, in particular to a switch for controlling the forward drive speed of a mower.

BACKGROUND OF THE INVENTION

Mowers are used extensively, both in the home and in public spaces, to maintain lawns. For larger areas of lawn, self-propelled mowers are typically used, especially in professional sport arenas, such as football, golf, cricket, bowls and the like.

Self-propelled mowers generally have motors that act to both turn a cutting blade (or typically a cutting cylinder) and to drive a rear roller that propels the mower. An exemplary conventional system uses a thumb operated proportional speed control lever in conjunction with a speed setting dial in order to control the speed during operation. Pressing the thumb lever increases the speed of the rear roller up to the pre-set speed on the speed setting dial. In such examples, both the thumb lever and speed setting dial are connected to potentiometers. In order to slow down the mower to make a turn the thumb lever is pressed. However, if the lever is pressed too far then the roller drive can be stopped, reducing the efficiency of the turn. Conversely as the thumb control is proportional, the user must remember the position that the thumb lever needs to be placed at in order to make a controlled turn. Often, during a turn, the thumb lever can moved to a position that drives the motor either too fast to make the turn compromising safety, or too slowly and productivity is lost.

Alternatively, some mowers use either a speed paddle to change drive speed or a bail bar. Both are proportional controls. Selecting an appropriate speed to make a turn is difficult. To slow down to make a turn on such self-propelled mowers, either the engine throttle must be altered, losing the currently set speed setting (which is typically a comfortable walking pace) or the traction clutch must be slightly disengaged to effectively slip the drive clutch to slow the mower down.

The present invention aims to at least ameliorate the aforementioned disadvantages with prior art mowers.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention, there is provided a mower comprising: a motor for driving the mower; a controller for controlling a speed of the motor; and a switch mounted on a handle or handlebar of the mower; wherein the switch is configured to signal the controller to alter the drive speed of the mower between a normal drive speed and at least one pre-set drive speed.

The present invention overcomes the issue of selecting a slower speed on the move and whilst making a turn by simplifying the speed reduction operation for the user.

Instead of trying to accurately find just the right position on a proportional speed control during each hurried turn, the present invention instead alters the mower drive speed to a pre-set value using a switch. The pre-set speed can be tailored to the user through the controller programming. It can be appreciated that the pre-set speed is typically a slower speed than the normal drive speed to aid the user in performing cornering or other manoeuvres more safely. Alternatively (or additionally if multiple pre-set drive speeds are utilised), the pre-set speed may be faster than the normal drive speed. This may be of use for long flat stretches of lawn, or for surfaces that require additional power to the drive of the mower, such as long grass or sloped lawns.

In an embodiment activation of the switch may alter the speed of the motor to the pre-set drive speed, whilst deactivation of the switch may revert the speed of the motor to the normal drive speed. Such dual state switches aid operation of the mower by minimising the control complexity for cornering or other slow speed manoeuvres, and for allowing reversion back to the original speed setting, to a dual state toggle. Alternatively it can be appreciated that the switch may be a multi-state switch, such as a rotary switch, allowing toggling or cycling through pre-set drive speeds as required by the user, before release of the switch reverts the mower to the normal drive speed. An electronic switch may be used, electrically coupled to the controller using a wireless communication protocol. Such switches may be virtual switches of a graphical user interface of an application running on an electronic screen of a mobile device. It can also be appreciated that such switches may be integrated with a screen on the mower.

In an embodiment, the mower may comprise one or more additional switches. In such examples each additional switch may be configured to signal the controller to alter the speed of the motor from the normal drive speed or from the pre-set drive speed to a second pre-set drive speed.

The normal drive speed may be controlled or selected using a potentiometer switch. In the present invention the normal drive speed may be decoupled from a drive switch used to commence movement of the mower.

The pre-set drive speed or speeds may be set at fixed percentages of the normal drive speed. For example, the switch may enable a pre-set drive speed at 50% of the normal drive speed, or at any percentage of the normal drive speed (within the normal operating capabilities of the motor). Example percentages of the pre-set drive speed include between 10% and 90%, between 20% and 80% or throttled to a maximum value of the normal speed, for example throttled to 75% of normal speed.

In one example the mower further comprises a battery for powering the motor. Types of battery typically include one or more batteries based on a Lithium-ion chemistry, although other battery chemistries may be selected depending on the voltage, capacity, weight and lifespan requirements. Such batteries are typically lighter than petrol engines. One motor may be used to drive the mower and any cutting means or other functionality on the mower, or a separate motor may be used to separately drive the cutting means (and/or also any additional functionality).

It can be appreciated that in such examples, reference to motors can include electric motors that provide power to drive means of the mower, and any cutter, and any other electronic functionality of the mower. In such examples the switch may be connected between the battery and the controller. Accordingly, activation of the switch may act to complete a connection between a positive terminal of the battery and a mode pin of the controller. In this manner, the controller may sense a voltage over the mode pin when the switch is activated.

In a preferred embodiment, the controller may comprise memory for storing a mode function, said mode function defining the one or more pre-set speeds. The memory may be non-volatile memory. The mode function may define how operation of the switch alters the normal drive speed or selects one or more of the pre-set drive speeds. The mode function may also allow a user configurable profile to be stored in the memory of the controller. The mode function containing the user configured profile may be recalled when the switch is activated.

In a further example, the mower may further comprise a rotating cutter driven by the or an additional motor for cutting grass or the like. The cutter may be a cylinder cutter or the like. In such embodiments a speed of rotation of the cutter may be independent of the drive speed. Accordingly, this allows the mower to continue cutting at the desired cutting speed even when cornering or performing other slower manoeuvres. Unlike in known mowers, decoupling of the rotation speed of the cutter from the drive speed of the mower allows cutting quality and efficiency to be tailored independently of the speed of the mower.

According to a second aspect of the present invention there is provided a method of discretely controlling the speed of a mower, said mower comprising a motor for driving the mower and a controller for controlling a speed of the motor, the method comprising the steps of: storing one or more pre-set speeds in a memory of the controller; activating a switch to provide a signal to the controller to set the speed of the motor to one of the pre-set speeds; and deactivating the switch to revert the motor to a normal drive speed.

These and other aspects of the invention will be apparent from, and elucidated with reference to, the embodiments described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiment of the invention shall now be described in detail by way of example and with reference to the accompanying drawings in which: Figure 1 illustrates components for a mower according to a preferred embodiment of the present invention; and Figure 2 illustrates a mower comprising the components of figure 1.

It should be noted that the figures are diagrammatic and not drawn to scale.

Relative dimensions and proportions of parts of these figures have been shown exaggerated or reduced in size, for the sake of clarity and convenience in the drawings. The same reference signs are generally used to refer to corresponding or similar feature in modified and different embodiments.

DETAILED DESCRIPTION OF EMBODIMENTS

In an exemplary embodiment of the present invention, as shown in figures 1 and 2 there is provided a system 100 for a mower. Figure 1 shows a broad overview of the components of the system 100. In particular, the system 100 comprises at least one motor 110 having drive means 120 for propelling the mower and for rotating cutting means. A controller 130 is provided, in communication with the motor for controlling the speed of the mower. Finally a switch 140 is used to provide a signal to the controller 130.

Broadly, one motor provides drive to the mower drive means, whilst another motor provides power to the cutting means. However, it may be appreciated that a single motor can provide both functionalities. For simplicity in the exemplary embodiment described below, a single motor is described. In a conventional petrol mower the motor can be a combustion engine -in this instance the motor also provides power to any electrical components on the mower. Alternatively (or potentially additionally) a battery may be used to power the motor and any electronics. The advances in battery chemistry, leading to improved battery capacities and voltage output has allowed mowers to remove combustion engines in some instances. When a pure battery is used to provide power to the mower, the motor is typically an electric motor. The electric motor may be a permanent magnet synchronous motor, or the like. In the example described herein, a battery and electric motor is used.

A detailed schematic of a mower 200 including the system 100 of figure 1 is shown in figure 2. A housing 210 is provided to contain the system. In figure 2, the motor 110, controller 130 and switch 140 are shown. Motor 110 is mechanically coupled to a rear drive means, in this instance a rear roller 220 to provide forward drive of the mower 200. The motor 110 is configured to supply a constant drive force to the rear roller 220 when fully actuated, resulting in a normal drive speed when the mower is used as intended on flat, straight stretches of lawn or the like.

Control of the motor 110 in relation to the drive speed of the rear roller 220 may use a throttle, which may be a thumb operated switch, pull (bail) bar, or other form of hold to actuate switch that ensures that motor operation is tied to an action of the user. Such switch may utilise proportional control up to the normal drive speed specified by the controller 130.

In the embodiment described, the motor 110 is also configured to drive rotation of a cutter 230, in the example shown in figure 2 a cylindrical drum comprising a series of cutting blades, which may be arranged in cartridges. It can be appreciated that alternative cutting means may be utilised, such as a rotary cutter depending on the style of mower. It can also be appreciated that a separate motor may be utilised to drive the cutter, as described above and below.

When a single motor is used, gearing (not shown) may be utilised to ensure that the cutter 230 rotates at a different speed to the rear roller 220 and/or to allow the cutter 230 to have a different throttle response upon actuation of the throttle such that the rotational speed of the cutter is essentially constant at all drive speeds.

In the example shown in figure 2, motor 110 is controlled by the controller 130. As noted above, the controller can allow for independent control of the rotational speed of the cutter 230 and the rear roller 220. Maintaining rotational speed of the cutter 230 allows for a more consistent and even cut of lawn even when the forward drive speed of the mower is reduced. It can be appreciated that use of a separate motor to drive the cutter 230 may reduce the need for such independent control.

A handle 240 is provided on the mower for housing the throttle and a proportional control 242 that allows adjustment of the normal drive speed of the mower by the user. The handle (which may be a handlebar or the like) is typically held by the user for throttle controlled mowers, or may be primarily used to house controls in walk-behind mowers. In the example shown, the handle 240 also houses the switch 140. The switch in the example shown is a simple dual state switch, like a rotary switch, although additional switches, or multi-state switches may be used depending upon how many pre-set drive speeds are available. Such dual state switches aid operation of the mower by further minimising the control complexity for cornering or other slow speed manoeuvres, and for reverting back to the original speed setting. In addition, such a configuration allows both hands of the user to remain in contact with the handle 240 whilst in a manoeuvring situation improving safety.

Additionally, as noted above, a battery 250 may be provided. In the disclosed example, the battery 250 is one or more multiple lithium-ion batteries, which provide high capacity, high output and light weight. The battery is electrically connected to the motor 110, which is an electric motor of the type described above. The switch 140 is also connected between the battery 250 and the controller 130.

In use the controller 130 acts to control the speed of the motor, which in turn controls the speed of the mower. In general the mower is set to a normal drive speed by the controller 130, in accordance with the value of the proportional control 242, which acts to control the voltage supplied to the motor 110 by the battery 250. This control may be by changing the value of the voltage supplied and/or the timing. The controller 130 may utilise pulse width modulation to control the output of the motor 110.

Additionally, the controller has one or more additional mode functions stored within memory of the controller. The mode functions define operating output parameters for the battery/motor. These operating output parameters alter the drive speed of the mower -in particular they allow the drive speed to be changed to one or more pre- set speeds. Such operating output parameters may enact a pre-set drive speed at 50% of the normal drive speed, or at any percentage of the normal drive speed (within the normal operating capabilities of the motor). Several pre-set drive speeds may be enacted by several mode functions. It can be appreciated that a lower pre-set speed aids the user in performing cornering or other manoeuvres more safely.

The mode functions are typically enacted using activation of the switch 140 to complete a connection between a positive terminal of the battery 250 and a mode pin of the controller 130. The controller is configured to sense a voltage over the mode pin when the switch 140 is activated. This allows the controller to determine which mode pin has been selected in the case of multiple switches, or for multi-state switches.

The mode functions may be defined by the mower manufacturer, or they may be defined by the user. For example, the user may define that selection of one pre-set reduces the output of the motor, causing the drive speed of the mower to slow to a defined pre-set level which is more suited for cornering or for avoiding hazards. The mower may be reduced to half speed for right angled turns, to third speed for 180 degree turns etc. In a similar manner, the mode functions can allow a user to alter the output of the motor to account for terrain changes. The output of the mower may be reduced for declines and increased for inclines, for example, to allow for a more consistent overall speed of the mower, without the need to manually maintain a throttle position.

Instead, the user merely selects the correct switch 140, or places the switch 140 into the correct state. Restoring the state of the switch 140 restores the operating conditions of the motor, with the mower resuming a normal drive speed.

From reading the present disclosure, other variations and modifications will be apparent to the skilled person. Such variations and modifications may involve equivalent and other features which are already known in the art of receivers and which may be used instead of, or in addition to, features already described herein.

Although the appended claims are directed to particular combinations of features, it should be understood that the scope of the disclosure of the present invention also includes any novel feature or any novel combination of features disclosed herein either explicitly or implicitly or any generalisation thereof, whether or not it relates to the same invention as presently claimed in any claim and whether or not it mitigates any or all of the same technical problems as does the present invention.

Features which are described in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. The applicant hereby gives notice that new claims may be formulated to such features and/or combinations of such features during the prosecution of the present application or of any further application derived therefrom.

For the sake of completeness it is also stated that the term "comprising" does not exclude other elements or steps, the term "a" or "an" does not exclude a plurality, a single processor or other unit may fulfil the functions of several means recited in the claims and reference signs in the claims shall not be construed as limiting the scope of the claims.

Claims

CLAIMS1. A mower comprising: a motor for driving the mower at a drive speed; a controller for controlling a speed of the motor; and a switch mounted on a handle or handlebar of the mower; wherein the switch is configured to signal the controller to alter the drive speed of the mower between a normal drive speed and at least one pre-set drive speed.
2. A mower according to claim 1, wherein activation of the switch alters the speed of the motor to the pre-set drive speed; and deactivation of the switch reverts the speed of the motor to the normal drive speed.
3. A mower according to claim 2, further comprising one or more additional switches, each additional switch configured to signal the controller to alter the speed of the motor from the normal drive speed or from the pre-set drive speed to a second pre-set drive speed.
4. A mower according to any preceding claim, further comprising a potentiometer switch for controlling the normal drive speed.
5. A mower according to any preceding claim, wherein the at least one pre-set drive speeds are fixed percentages of the normal drive speed.
6. A mower according to any preceding claim, further comprising a battery for powering the motor, and wherein the switch is connected between the battery and the controller.
7. A mower according to claim 6, wherein activation of the switch completes a connection between positive terminal of the battery and a mode pin of the controller.
8. A mower according to claim 7, wherein the controller senses a voltage over the mode pin when the switch is activated.
9. A mower according any preceding claim, wherein the controller comprises memory for storing a mode function, said mode function defining the one or more pre-set speeds.
10. A mower according to claim 9, wherein the mode function allows a user configurable profile to be stored in the controller's memory.
11. A mower according to claim 9, wherein the mode function containing the user configured profile is recalled when the switch is activated.
12. A mower according to any preceding claim, further comprising a rotating cutter driven by the or an additional motor, and wherein a speed of rotation of the cutter is independent of the drive speed.
13. A mower according to claim 12, wherein the cutter is a cylinder cutter.
14. A method of discretely controlling the speed of a mower, said mower comprising a motor for driving the mower and a controller for controlling a speed of 20 the motor, the method comprising the steps of: storing one or more pre-set speeds in a memory of the controller; activating a switch to provide a signal to the controller to set the speed of the motor to one of the pre-set speeds; and deactivating the switch to revert the motor to a normal drive speed.