A power tool system

Abstract

A power tool system comprising two or more power tools 101, 201 capable of operating in any one of three modes. In the first mode, each power tool independently operates such that it can be directly m

Description

A power tool system [1] The present invention relates generally to handheld power tools and finds particular, although not necessarily exclusive, utility in portable handheld power tools. [2] By their nature power tools can be awkward to use in situations where access is restricted. For instance, it can be particularly difficult when there is insufficient space for more than one hand to operate a power tool. In this case, often the user's hand has to apply significant forces to keep the power tool working in the required position and location whilst at the same time also accessing and operating the said power tool's controls. Bi Accordingly, it is desirable to provide a system whereby the controls of a power tool can be operated remotely. Furthermore, it is also desirable for the user of the first power tool to use another power tool as the controller to remotely operate the first power tool. Preferably a power tool that would normally be carried with and be operated by a power tool user, perhaps as part of a set. Further, it is desirable for the power tool operating as the controller to be easy to operate. [4] Accordingly, the invention provides a system whereby the operator can use one power tool, to control just itself, or to control one or more other power tools, or it can control a combination of itself and one or more other power tools together, as required. [5] The power tools may be whole single-task power tools or motor handles, without tool heads, or where applicable, with tool heads, or any combination appropriate for the application. [6] In a first aspect, the invention may provide two or more power tools, for instance 2 to 2000, each may be designed or adapted to include either a remote control transmitter or a receiver, or both, or a transceiver or a transmitter-receiver, as desired. Each motor handle may or may not also be attached to a tool head as desired. [7] It is envisaged that the power tools may need to work in different modes according to the application requirements of the operator. [8] At least three possible operating modes (A) are contemplated for a remote controlling power tool equipped with a transmitter, although it should be understood that not necessarily all modes need be included, that any combination may be used or arranged in any sequence, the number of modes is not limited and further modes are contemplated. The operating mode may be selected by a switching arrangement and may include: [9] Mode 1A: transmitter to control remote power tools switched off; direct local control of the motor drive of the controlling power tool switched on.

[10] Mode 2A: transmitter switched on to control drive by each of a required number of remote power tools, for instance between 1 and 1000 at any time, each equipped with a receiver; direct local control of the motor drive of the controlling power tool switched off.

[11] Mode 3A: transmitter switched on to control drive by each of a required number of remote power tools, for instance between 1 and 1000 at any time, each equipped with a receiver; direct local control of the motor drive of the controlling power tool also switched on.

[12] Further modes are contemplated including, for instance, arranging the transmitter to control the local motor drive in the transmitter equipped power tool individually or in combination with each remote receiving power tool, depending on the combinations of transmitters and receivers or transceivers or transmitter-receivers installed in the power tools and the operating arrangements adopted.

[13] At least three possible operating modes (B) are contemplated for each of a required number of remote controllable power tools, for instance between 1 and 1000 at any time, although it should be understood that not necessarily all modes need to be included, that any combination may be used or arranged in any sequence, the number of modes is not limited and further modes are contemplated. The operating mode may be selected by a switching arrangement and may include:

[14] Mode 1B: receiver switched off; direct local control of the remote controllable power tools or power tools switched on.

[15] Mode 2B: each receiver switched on to receive remote instructions and control drive to each of a required number of remote controllable power tools, for instance between 1 and 1000 at any time; direct local control of the controllable power tool or power tools switched off.

[16] Mode 3B: receiver switched on to receive remote instructions and control drive to each of a required number of remote controllable power tools, for instance between 1 and 1000 at any time; direct local control of the remote controllable power tool or power tools also switched on.

[17] Further modes are contemplated including, for instance, arranging the receiver to control the local motor drive in the receiver equipped power tool individually or in combination with other remote receiving power tools or the transmitting power tools, or a combination, depending on the selection of transmitters and receivers or transceivers or transmitter- receivers installed in the power tools and the operating arrangements adopted.

[18] In addition to controlling the throttle or throttles or on-off switching, or a combination, according to the above modes, it may be desirable to include arrangements that may include additional channels and servo or solid state electronic switching, or both, to remote control the position or state of the forward-reverse switching or locking, or both, of the on-off switch or throttle, or both, in the off position so that the motor will operate in the desired rotation or will not operate unintentionally, respectively, or both. The solid state electronics may be arranged to over-ride or bypass the manual forward-reverse switch or the locking of the on-off switch or throttle, or a combination, on the receiving power tool or power tools.

[19] The transmitter and receivers may be arranged to operate single or multiple channels. For instance, a system comprising two meterhandies, power tools each with simple on-off switches, may use a single channel remote control system. A system comprising two power tools, each with on-off switches and forward-reverse switches, may use a two channel remote control system. A system comprising two power tools, each with variable speed throttles and forward-reverse switching and throttle trigger locking means, may also use a two channel remote control system or a three channel remote control system.

[20] The transmitters and receivers, as discussed above, may use a remote control system capable of very simple on-off or binary control. Or they may use a remote control system capable of variable or proportional control. Or they may use a combination of binary and proportional remote control systems.

[21] Each transmitting power tool may be arranged to operate in a similar manner to a conventional power tool whereby the power on and off, the speed adjustment, if included; and forward-reverse, if included; may be controlled by a trigger type switch or trigger type throttle or a cross-sliding type switch, respectively, or a combination, located in a convenient to operate position, for instance, the neck area of the tool as adopted by many conventional power tools.

[22] The throttle trigger of each transmitting power tool may include a speed controlling device such as a potentiometer, rheostat, resistor array, sensor arrangement, other alternative or a combination. The speed controlling device may be used to control more than one power tool, directly or indirectly. For instance, in the case of two power tools, one speed controlling device may be used to control the motor of one power tool directly, or indirectly via a control unit, whilst, at the same time, it may control the motor of the second power tool via a transmitted and received signal directly, or indirectly via another control unit in the second power tool.

[23] Alternatively, the throttle trigger of the transmitting power tool may include more than one speed controlling device such as potentiometers, rheostats, resistor arrays, sensor arrangements, other alternatives or a combination. For instance, in the case of two power tools, one speed controlling device may be used to control the motor of one power tool directly, or indirectly via a control unit, whilst another speed controlling device may be included to control the motor of the second power tool via a transmitted and received signal directly, or indirectly, via another control unit in the second power tool.

[24] The mode switching arrangement may be manually operated by a simple switch, which may be a switch with multiple settings, or it may be a series of switches, or it may be arranged to operate automatically, or it may be a combination.

[25] The remote control transmitting and receiving system may use analogue or digital or any other remote control technology.

[26] The remote control transmitting and receiving system may use radio control, in which case it may utilise various radio frequencies.

[27] The remote control transmitting and receiving system may use infrared control, in which case it may utilise various frequencies.

[28] The remote control transmitting and receiving system may use ultrasonic control, in which case it may utilise various frequencies.

[29] The remote control transmitting and receiving system may be wired with cables, which may be flexible, and may be connected between each power tool via removable or fixed connectors, or a combination.

[30] The remote control transmitting and receiving system may use a combination of any of the above control means or mediums.

[31] The remote control transmitting and receiving system may use any other control means or medium that may be applicable or appropriate, individually or in combination with the above control means or mediums.

[32] In the first aspect the invention is intended to apply to power tools of all types that may or may not be of the fixed whole single-task type and may include at least two power tools, which may be of a similar or a dissimilar type, which may be designed or adapted so as to incorporate a transmitter in one, so as to be able to control, and a receiver in at least one other, so as to be remotely controllable, as considered appropriate for the application.

[33] In a second aspect the invention is applied to power tools of the types discussed in the first aspect with tools.

[34] In another embodiment the invention may be applied to power tools of all types so that they may work together. They may or may not be of the fixed whole single-task type. The combination of power tool systems may include at least two power tools, which may be of a similar or a dissimilar type, which may be designed or adapted so as to incorporate a transmitter in one, so as to be able to control, and a receiver in one or more other, so as to be remotely controllable, as considered appropriate for the application.

[35] In a further embodiment the controlling device that includes a transmitter device may take a different form, for instance, it may be a control handle of the type used for radio control of models, or a joystick pad or a suitably adapted mobile phone.

[36] In all embodiments mentioned above each transmitter and each receiver may be substituted with a transceiver, or a transmitter-receiver or both a transmitter and a receiver, as considered appropriate for the application.

[37] In the case of an alternative embodiment, where the remote control transmitting and receiving system may be wired with cables connected between each power tool via removable or fixed connectors, or both, there may not be any need for specific transmitters and receivers. Instead, it may be preferable simply to equip the controlling power tool with two speed controlling throttle control units arranged to work in parallel, one operating directly to the motor or motor control unit in the controlling power tool, and one operating via the cable wired and connected between the controlling and controlled power tools.

[38] In the case of a further alternative embodiment, it may be desirable to include only some of the modes and functions discussed in the first aspect above, particularly in power tools not having removable tool heads.

[39] In a further aspect, the invention may provide a handheld power tool system according to the first aspect and tools attached thereto.

[40] The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. This description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

[41] Figure 1 is a schematic side view of a drill type power tool.

[42] Figure 2 is a schematic side view of a second drill type power tool.

[43] Figure 3 is a schematic side view of two drill type power tools, each shown with a rotating chuck indicated.

[44] Figure 4 is a schematic side view of two power tools being held manually, each shown with a rotating chuck indicated.

[45] Figure 5 is a schematic side view of two power tools, each of a drill type. The left side power tool is shown with a rotating chuck indicated whilst at the same time transmitting radio signals to the right side power tool, which is also shown with a rotating chuck indicated.

[46] Figure 6 is a schematic side view of two power tools, each of a drill type. The left side power tool is shown being held manually whilst at the same time transmitting radio signals to the second power tool which is also being held manually. Both power tools are shown with rotating chucks indicated.

[47] The present invention will be described with respect to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. Each drawing may not include all of the features of the invention and therefore should not be considered to be an embodiment of the invention. In the drawings, the size of some of the elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

[48] Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequence, either temporally, spatially, in ranking or in any other manner. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other sequences than described or illustrated herein.

[49] Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that operation is capable in other orientations than described or illustrated herein.

[50] It is to be noticed that the terms ‘include’ and ‘includes’, used in the claims, should not be interpreted as being restricted to the means listed thereafter; they do not exclude other elements or steps. They are thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but do not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression ’a device includes means A and B’ should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B.

[51] Similarly, it is to be noticed that the term ‘connected’, used in the description, should not be interpreted as being restricted to direct connections only. Thus, the scope of the expression ’'a device A connected to a device B’ should not be limited to devices or systems wherein an output of device A is directly connected to an input of device B. It means that there exists a path between an output of A and an input of B which may be a path including other devices or means. ‘Connected’ may mean that two or more elements are either in direct physical or electrical contact, or that two or more elements are not in direct contact with each other but yet still co-operate or interact with each other.

[52] Reference throughout this specification to ’an embodiment’ or ‘an aspect’ means that a particular feature, structure or characteristic described in connection with the embodiment or aspect is included in at least one embodiment or aspect of the present invention. Thus, appearances of the phrases in one embodiment’, ‘in an embodiment’, or ‘in an aspect’ in various places throughout this specification are not necessarily all referring to the same embodiment or aspect, but may refer to different embodiments or aspects. Furthermore, the particular features, structures or characteristics of any embodiment or aspect of the invention may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments or aspects.

[53] Similarly, it should be appreciated that in the description various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Moreover, the description of any individual drawing or aspect should not necessarily be considered to be an embodiment of the invention. Rather, as the following claims reflect, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

[54] Furthermore, while some embodiments described herein include some features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form yet further embodiments, as will be understood by those skilled in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[55] In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practised without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

[56] In the discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

[567] The use of the term "at least one" may mean only one in certain circumstances.

[58] The principles of the invention will now be described by a detailed description of at least one drawing relating to exemplary features of the invention. It is clear that other arrangements can be configured according to the knowledge of persons skilled in the art without departing from the underlying concept or technical teaching of the invention, the invention being limited only by the terms of the appended claims.

[59] Figure 1, shows a power tool 100, which may be a drill with a chuck 105 attached. The trigger 110 may be connected to and operate a speed control throttle arrangement 120 or on-off switch or combination thereof, which may, for instance, be connected by wiring 130 to a power control unit 150 which may control a motor 155 with an output driveshaft, not shown. A switch 140 may be connected to the power control unit 150 so that an operating mode may be selected by moving the position of the switch. There may, for instance, be three operating modes and three switch positions. The trigger 110, the speed control throttle unit 120, which may each include more than one speed control arrangement, and the switch 140 may also be connected to a transmitter unit 160 which may have an aerial 190 attached.

[60] It should be understood that in the following descriptions and the claims the term ‘whole single-task power tool’ refers to a power tool of the type that has the tool head incorporated with the motor and controls, along with other features, in or on one fixed body, so that the tool head is not interchangeable. For instance a power tool of the type that has the drill tool head incorporated with the motor and controls, and other features, in or on one fixed body, may be known as a whole single-task power drill.

[61] Figure 2, shows a power tool 200, which may be a drill with a chuck 205 attached. The trigger 210 may operate a speed control throttle unit 220 or switch or combination thereof, which may be connected, for instance, by wiring 230 to a power control unit 250 which may control a motor 185 with an output driveshaft, not shown. A switch 240 may be connected to the control unit 250 so that an operating mode may be selected by moving the position of the switch, for instance there may be three operating modes and three switch positions of which one mode may require the switch position to be off. The trigger 210, the speed control throttle unit 220, which may each include one or more throttle arrangement, and the switch 240 may also be connected to a receiver unit 270 which may have an aerial 290 attached.

[62] The power tools in Figures 1 and 2 may each include, as an alternative to one having a transmitter 160 and the other having a receiver 270, a combination of a transmitter 160 and a receiver 270, which may be a transceiver or transmitter-receiver or a combination, so that the power tools, so equipped may be used interchangeably.

[63] Figures 3 and 4, each show two power tools, 100 and 200, which may each be a single task power tool, as illustrated, or they may each be a motor handle 101 and 201 and a tool head 102 and 202, or they may be one or more of each, in which case they may be arranged so that it does not matter which is which.

[64] In Figures 3 and 4, each power tool, 100 and 200, may be a power drill, as shown in Figure 3, and each may have its mode switch, 140 and 240 respectively, set to a mode setting that may correspond to Mode 1A and 1B respectively, discussed above, so that each power drill may be individually controllable by manual operation by, for instance, its throttle switch trigger 110 and 210, as shown in Figure 4, to regulate the rotation of its output chuck 105 and 205, respectively, as required. The rotation of the chucks 105 and 205 may, for instance, be clockwise, as indicated by the curved arrows, or they may be anticlockwise, as required.

[65] Figures 5 and 6, each show two power tools, 100 and 200, which may, for instance, each be a power drill, as illustrated. Each power tool may have a mode switch, 140 and 240 respectively, which may be set to a mode setting that may correspond to Mode 2A and 2B respectively, as discussed above, so that the controls of power tool 100 may control the power drill 200 by remote control means. Power tool 100 may transmit radio control signals 1000 and power drill 200 may receive and be controlled by them.

[66] Figures 7 and 8, each show two power tools, 100 and 200, which may, for instance, each be a power drill, as illustrated. Each power tool may have a mode switch, 140 and 240 respectively, which may be set to a mode setting that may correspond to Mode 3A and 3B respectively, as discussed above, so that the controls of power tool 100 may be used to control both power tool 100, for example directly via cable 130, which may be inside, see Figure 1, and power tool 200 by remote means, which may be by transmitting radio control signals 1000 which power drill 200 may receive and be controlled by.

[67] It should be understood that whilst the power tools shown as examples in the Figures and discussed in the above descriptions may be whole single-task power drills it is contemplated that they may take other forms. That is to say that the power drills may be substituted with any appropriate alternative power tool or power tools, or combination thereof, designed or adapted to be equipped, as necessary, to operate in the various modes discussed and as desired. It is envisaged that any alternative power tool or power tools may include but not be limited to, for instance, any type of motor handle or power handle, with or without a tool head and with or without a motor, each power tool or tool head may also include or not include a motor; a drill; an impact driver; a grinder; a sander; a planer; a saw; a multi-tool; or any other type of power tool or power tools or suitably configurable pieces of equipment designed or adapted to be equipped, as necessary, to operate in the various modes discussed and as desired singly or in plurality.

[68] It should also be understood that whilst the number of power tools shown in the Figures 3 to 10, inclusive, is two, any number of power tools is contemplated, for instance between 1 and 1000 power tools may be controlled by between 1 and 1000 other power tools together or separately. Each power tool suitably equipped with the appropriate remote control transmitter or receiver or combination, as necessary.

[69] It should further be understood that whilst the power tools shown in the Figures are battery power tools, any other form of power tool is contemplated, including mains electricity powered, via cable; air powered or any other power source or medium.

[70] It should also be understood that the number of modes and the number of switch positions may be more or less than three according to how many modes are required and that they may be arranged in any order desired or found to be appropriate for an application.

Claims

A power tool system CLAIMS [1] 1. A power tool system includes two or more power tools (100 and 200) characterised in that each is configured for a user to operate them in three possible control modes: 1, direct manual control of each power tool (100 and 200) so that each can operate separately; 2, remote control by one power tool (100), which itself does not otherwise operate, of one or more other power tools (200); 3, a combination of modes 1 and 2 whereby there is direct manual control of one power tool (100), so that it operates, and simultaneously remote control by the same power tool (100) of one or more other power tools (200). [2] 2. The power tool system of claim 1, includes whole single- task power tools (100) that are equipped to remotely control other power tools (200) that are equipped to be so controlled. [3] 3. The power tool system of any preceding claims, further includes a multi-way switch on each power tool (100 and 200) arranged so that the desired control mode can be selected according to the setting of the switch. [4] 4. The power tool system of any preceding claims, further includes remote control means which utilise radio signals. [5] 5. The power tool system of claims 1, 2 or 3, includes remote control means which utilise ultrasonic signals. [6] 6. The power tool system of claims 1, 2 or 3, includes remote control means which utilise infrared signals. [7] (. The power tool system of claims 1, 2 or 3, includes remote control means which utilise any other workable signals. [8] 8. The power tool system of claims 1, 2 or 3, includes remote control means which utilise any combination of signal types. [9] 9. The power tool system of claims 1, 2 or 3, includes remote control means which utilise attachable and removable control wiring that can be arranged to be connected between the motor handles or power tools or both. [10] 10. The power tool system of any claims 1, 2 or 3, includes remote control means which can utilise binary or proportional control types or any combination of control types. [11] 11. The power tool system of claims 1, 2 or 3, includes remote control means which utilise digital or analogue signals or a combination. [12] 12. The power tool system of any preceding claims, further includes remote control means that can have more than one channel. [13] 13. The power tool system of any preceding claims, further includes remote control means with a channel for speed control or control of an on-off means, or both. [14] 14. The power tool system of any preceding claims further includes remote control means with a channel for forward-reverse control, or a means for locking of the speed control or on-off throttle trigger (110) in the off position, or any combination. [15] 15. The power tool system of any preceding claims, further includes remote control means that can utilise a combination of any of the control means and mediums in the preceding claims. [16] 16. The power tool system of any preceding claims, further includes control means that include a transmitter device in each controlling power tool (100) and a receiver device in each controlled power tool (200). [17] 17. The power tool system of any preceding claims, wherein the transmitter and receiver devices can be replaced with transceivers or transmitter-receivers so that each power tool (100 and 200) can be operated interchangeably as the controlling or controlled tool or tools. [18] 18. The power tool system of any preceding claims, wherein the throttle trigger (110) of each controlling power tool (100) is arranged to be the primary speed or on-off control actuator means, or both. [19] 19. The power tool system of any preceding claims, wherein a manual slide switch, if fitted, is arranged to be the primary forward- reverse or throttle trigger (110) lock control actuator means, or both, for each controlling power tool (100). [20] 20. The power tool system of any preceding claims, wherein a manual slide switch, if fitted to the controlling power tool, can be arranged to be the primary forward-reverse or throttle trigger (110) lock control actuator means, or both, for each controlled power tool (100). [21] 21. The power tool system of any preceding claims, wherein the forward-reverse controlling power tool (100) can be arranged to bypass or over-ride, or both, the forward-reverse setting of each remotely controlled power tool (200), if necessary, so as to ensure that all power tools (100 and 200) rotate in the same required direction. A power tool system CLAIMS [1] 1. A power tool system includes two or more handheld power tools (100 and 200) characterised in that each is configured for a user to operate them in three possible control modes: 1, direct manual control of each power tool (100 and 200) so that each can operate separately; 2, remote control by one power tool (100), which itself does not otherwise operate, of one or more other power tools (200); 3, a combination of modes 1 and 2 whereby there is direct manual control of one power tool (100), so that it operates, and simultaneously remote control by the same power tool (100) of one or more other power tools (200). [2] 2. The power tool system of claim 1, includes whole single- task power tools (100) that are equipped to remotely control other power tools (200) that are equipped to be so controlled. [3] 3. The power tool system of any preceding claims, further includes a multi-way switch on each power tool (100 and 200) arranged so that the desired control mode can be selected according to the setting of the switch. [4] 4. The power tool system of any preceding claims, further includes remote control means which utilise radio signals. [5] 5. The power tool system of claims 1, 2 or 3, includes remote control means which utilise ultrasonic signals. [6] 6. The power tool system of claims 1, 2 or 3, includes remote control means which utilise infrared signals. [7] (. The power tool system of claims 1, 2 or 3, includes remote control means which utilise any other workable signals. [8] 8. The power tool system of claims 1, 2 or 3, includes remote control means which utilise any combination of signal types. [9] 9. The power tool system of claims 1, 2 or 3, includes remote control means which utilise attachable and removable control wiring that can be arranged to be connected between the power tools. [10] 10. The power tool system of any claims 1, 2 or 3, includes remote control means which can utilise binary or proportional control types or any combination of control types. [11] 11. The power tool system of claims 1, 2 or 3, includes remote control means which utilise digital or analogue signals or a combination. [12] 12. The power tool system of any preceding claims, further includes remote control means that can have more than one channel. [13] 13. The power tool system of any preceding claims, further includes remote control means with a channel for speed control or control of an on-off means, or both. [14] 14. The power tool system of any preceding claims further includes remote control means with a channel for forward-reverse control, or a means for locking of the speed control or on-off throttle trigger (110) in the off position, or any combination. [15] 15. The power tool system of any preceding claims, further includes remote control means that can utilise a combination of any of the control means and mediums in the preceding claims. [16] 16. The power tool system of any preceding claims, further includes control means that include a transmitter device in each controlling power tool (100) and a receiver device in each controlled power tool (200). [17] 17. The power tool system of any preceding claims, wherein the transmitter and receiver devices can be replaced with transceivers or transmitter-receivers so that each power tool (100 and 200) can be operated interchangeably as the controlling or controlled tool or tools. [18] 18. The power tool system of any preceding claims, wherein the throttle trigger (110) of each controlling power tool (100) is arranged to be the primary speed or on-off control actuator means, or both. [19] 19. The power tool system of any preceding claims, wherein a manual switch is arranged to be the primary forward-reverse or throttle trigger (110) lock control actuator means, or both, for each controlling power tool (100). [20] 20. The power tool system of any preceding claims, wherein a manual switch fitted to the controlling power tool, can be arranged to be the primary forward-reverse or throttle trigger (110) lock control actuator means, or both, for each controlled power tool (100). [21] 21. The power tool system of claims 19 and 20, wherein the forward-reverse controlling power tool (100) can be arranged to bypass or over-ride, or both, the forward-reverse setting of each remotely controlled power tool (200), if necessary, so as to ensure that all power tools (100 and 200) rotate in the same required direction.