Motion transmitting leg for rocking bed

Abstract

A motion transmitting leg 10, 100 for imparting oscillatory or reciprocating rectilinear motion to a bed to rock the bed. The motion transmission leg 10, 100 comprises a base 12, an upper part 14 movable relative to the base 12 for transmitting an oscillating or reciprocating linear motion, a linear axis motor 16 for driving the upper part 14 to move, a position sensing device 36 for determining the position of the linear axis motor 16 or the position of the upper part 14, and a motor controller for controlling the linear axis motor 16 in accordance with data from the position sensing device 36.

Description

Technical Field

[0001] The present invention relates to a motion transmitting leg for rocking a bed, and in particular but not exclusively to a motion transmitting leg for transmitting oscillating or reciprocating linear motion. Background Art

[0002] As is well known, one or more powered rocking legs or sliders are provided under or as replacement legs for conventional bed legs. These rocking legs or sliders provide the bed with forward and backward motion, such as a rocking motion that helps some people fall asleep.

[0003] The applicant's published patent application GB2610164 discloses an example of a leg that allows a bed to rock. However, mechanical components in current rocking legs that produce linear motion still cause problems. For example, problems with the accuracy of the linear motion or wear of components over time can cause noise and / or vibration.

[0004] The components of the rocker legs also require periodic maintenance. The ball screws (which convert the rotational motion of a standard electric motor into translational motion) need to be lubricated from time to time to keep the rocker legs working properly. However, home users often fail to oil the components themselves and may not follow the recommended professional maintenance regime. This can lead to component wear and other mechanical problems that affect the rocking of the bed.

[0005] The multiple legs used to make the bed rock need to be perfectly aligned with each other in order to operate. Therefore, special care and attention are required to attach the legs to the bed frame or bed legs. In some cases, such as a bed frame made of wood, which may deform over time, this deformation will also cause the modified rocking legs to be out of alignment. This means that the rocking legs need to be realigned and installed under the bed before normal use.

[0006] It is an object of the present invention to reduce or substantially eliminate the above mentioned problems. Summary of the invention

[0007] According to a first aspect of the present invention, there is provided a motion transmitting leg for transmitting oscillation or reciprocating linear motion to a bed so as to make the bed rock, the motion transmitting leg comprising:

[0008] Pedestal;

[0009] An upper member movable relative to the base for transmitting oscillatory or reciprocating linear motion;

[0010] A linear axis motor for driving the upper component to move linearly, the linear axis motor comprising a fixed portion and a movable portion spaced apart therefrom, the movable portion being movable linearly relative to the fixed portion;

[0011] A position sensing device for determining the position of the linear axis motor or the position of the upper member; and

[0012] A motor controller for controlling a linear axis motor based on data from a position sensing device.

[0013] Rectilinear motion can be thought of as a forward-backward translational motion in the horizontal plane of the motion-transmitting leg.

[0014] The moving part of the linear axis motor includes a housing and a coil wound inside the housing. The fixed part is a shaft that includes a plurality of magnets disposed inside the shaft along the length of the shaft.

[0015] Advantageously, the use of a linear axis motor eliminates the need to transform or convert the rotary motion of a standard rotary motor into translational or linear motion. This is because the motion of the linear axis motor can be used directly to cause motion of the upper member. This reduces the number of components required to couple the motor to the upper member, thereby making the design of the motion transmitting leg simpler.

[0016] Furthermore, there is no contact or friction between the moving and fixed parts of a linear axis motor. Therefore, there is no stuttering in the motor. This makes the motor noiseless and highly accurate. This also reduces manufacturing and maintenance costs because it eliminates the need for ball screws that require periodic or constant lubrication to prevent wear.

[0017] The upper member can be arranged above the linear axis motor. The upper member does not need to be connected to the threaded rod connected to one end of the motor shaft to make the upper member move linearly. The upper member does not need to be arranged at one end of the motor, thereby making the motion transmission leg more compact.

[0018] The linear motion path of the upper member may extend along the length of the fixed portion of the linear axis motor. In some embodiments, the linear motion path of the upper member may extend along the entire length of the fixed portion of the linear axis motor. This enables the upper member to move forward and backward along the motor. This also helps to keep the motion transfer leg compact because the motion path of the upper member does not exceed the length of the motor.

[0019] The upper member may be adapted to be displaced in a horizontal plane such that the upper member rotates and translates relative to the base.

[0020] In some embodiments, the upper member can rotate about a vertical axis of the motion transferring leg by approximately a few degrees, for example, up to 5 degrees, up to 10 degrees, or up to 15 degrees.

[0021] In certain embodiments, the upper member may translate up to 2 millimeters from its undisplaced position.

[0022] Advantageously, this allows the angle of the upper member relative to the base to be changed. Thus, when multiple motion transmitting legs are connected to a bed frame or legs of a bed frame, the motion transmitting legs do not need to be perfectly aligned with each other to work together. This is particularly useful when the bed frame deforms over time causing the motion transmitting legs to become misaligned.

[0023] In some embodiments, the upper member may include a flexible or resilient member. The flexible or resilient member may be made of an elastomeric material, such as rubber. This enables the upper member to rotate about the vertical axis of the motion transmitting leg or to tilt or change the orientation of the upper member.

[0024] In certain embodiments, the entire upper member may be a flexible or resilient member.

[0025] The motion transmitting leg may further include a linear motion assembly so that the linear motion of the linear axis motor causes the linear motion of the upper member.

[0026] The linear motion assembly may be disposed between the upper member and the moving portion of the linear axis motor.

[0027] The linear motion assembly may be coupled to the upper member and the moving portion of the linear axis motor.

[0028] The flexible or resilient member may be a portion of the upper member that is coupled to the linear motion assembly.

[0029] A fastening device may be provided to secure the linear motion assembly and the upper component together. This further ensures that the upper component and the linear motion assembly are securely connected to each other.

[0030] The fastening device may extend through the upper member and the linear motion assembly. The fastening device may be a bolt or a screw.

[0031] The linear motion assembly may include a recess for accommodating at least a portion of the moving portion of the linear axis motor. This enables the linear motion assembly to be mounted around the linear axis motor and further enables the motion transmitting leg to have a compact design.

[0032] The linear motion assembly may include a carriage and a linear slide assembly.

[0033] In some embodiments, the carriage may form the top of the linear motion assembly. The linear slide assemblies may form the sides of the linear motion assembly.

[0034] In some embodiments, the carriage may form an upper portion of the top and side portions of the linear motion assembly. The linear slide assembly may form a lower portion of the side portion of the linear motion assembly.

[0035] The linear slider assembly may include a first slider element coupled to each side or end of the carriage and a second slider element coupled to the base. This allows each second slider element to act as a guide rail and each first slider element to act as a movable block received on the guide rail. This provides linear motion of the linear motion assembly.

[0036] In some embodiments, each second slider element may be disposed between the linear axis motor and its corresponding first slider element.

[0037] Each first slider element may be generally T-shaped. Each T-shaped first slider element may have a first portion and a second portion extending perpendicularly from a center of the first portion.

[0038] One end of the first part of each T-shaped first slider element may be disposed close to or facing the base.

[0039] Each second slider element may be generally U-shaped. Each U-shaped second slider element may have two arms connected together.

[0040] One of the arms of each U-shaped second slider element may be arranged close to and abut the base. The outer surface of the arm may abut the base.

[0041] The second part of each T-shaped first slider element may be arranged to be linearly movable between the arms of its corresponding U-shaped second slider element.

[0042] A set of magnets may be provided on the linear motion assembly to bear the weight applied to the upper member and maintain the linear motion of the linear motion assembly.

[0043] At least one first carriage magnet may be provided for each first slider element.At least one second carriage magnet may be provided for each first slider element.

[0044] At least one base magnet may be provided for each second slider element.

[0045] At least one first carriage magnet may be disposed to a lateral side of at least one base magnet. The at least one first carriage magnet assists in maintaining linear motion of the linear motion assembly.

[0046] The at least one second carriage magnet may be arranged above or below the at least one base magnet. The at least one second carriage magnet and the at least one base magnet together enable the weight of the bed to be borne by the motion transfer legs.

[0047] The at least one first carriage magnet and the at least one second carriage magnet may be spaced apart from the at least one base magnet. In other words, a gap may be provided between the at least one first carriage magnet and the at least one second carriage magnet and the at least one base magnet.

[0048] The gap between the magnets means there is no contact or friction between the first and second slider elements. This helps prevent wear on the linear motion assembly and eliminates the need for maintenance or repairs.

[0049] The at least one first carriage magnet, the at least one second carriage magnet and / or the at least one base magnet may be a permanent magnet and / or an electromagnet.

[0050] The linear axis motor may be spaced apart from the base.

[0051] The position sensing device may be mounted below the linear axis motor. The position sensing device may be disposed in a space between the linear axis motor and the base. The position sensing device may be mounted to the base.

[0052] Alternatively, the position sensing device can be arranged at any position between the moving part and the fixed part of the motion transmitting leg or between the parts. That is, the position sensing device can be arranged at any suitable position for sensing the relative position of the moving part and the fixed part of the leg.

[0053] The position sensing means may comprise a linear encoder for encoding the position of the upper member.

[0054] Linear encoders provide precise positioning for low speed, high torque applications. They also have the advantage of improving synchronization when the leg is used with other motion transmitting legs.

[0055] A shield may be provided. The shield may substantially surround at least some components of the motion transmitting leg. For example, the shield may enclose the linear axis motor, the upper component, and the linear motion assembly.

[0056] The shield may be connected to the upper part. Fixing means may be provided to connect the shield to the upper part. This enables the shield to move linearly with the upper part and / or be displaced with the upper part in a horizontal plane.

[0057] A bed mounting bracket may be provided. The bed mounting bracket may be removably coupled to the upper member and / or the shield. The bed mounting bracket may couple the motion transfer leg to a bed frame or bed leg of the bed.

[0058] A bed coupling device may be provided in the bed mounting bracket. The bed coupling device may provide a coupling device for coupling to a standard bed frame or bed leg, for example, screw holes may be provided for coupling to a solid wood bed frame or bed leg. In other examples, a clamp, gripping member or similar member may be provided for coupling to a metal bed frame or bed leg, particularly a hollow bed frame or bed leg.

[0059] The motor controller can be configured to use field oriented control, also known as vector control. This provides very accurate position accuracy.

[0060] The motor controller may include communication means for receiving data from and / or sending data to a central control hub or similar motion transfer leg.

[0061] The communication means may include a wired communication port.

[0062] A safety system may be provided. The safety system may be configured to monitor for unexpected operation of the motion transfer leg.

[0063] The safety system may be configured to generate a warning signal based on unexpected operation of the motion-transmitting leg. The warning signal may be transmitted to a central control hub.

[0064] The safety system may be provided in the motion transmitting leg.

[0065] The motor controller may include the safety system.

[0066] The safety system may be configured to monitor for a decoupling (or lack of synchronization) between the intended movement that may be generated by the linear axis motor moving part (coil block) and the actual displacement performed by the coil block (connected to the upper part).

[0067] For example, the safety system can monitor if the position of the upper component becomes out of sync with the expected or desired position indicated by the motor controller. This can occur if the displacement or motion of the linear axis motor is blocked by an obstacle, the motor coils burn out, or the connecting wires become disconnected, among other possible events.

[0068] The safety system can be configured to generate a decoupling warning signal upon determining that there is a decoupling between the intended motion of the linear axis motor and the motion actually performed. The decoupling warning signal can be used to shut down the motion transfer leg.

[0069] Decoupling may be indicated by a difference between the expected position of the upper component and the actual position of the upper component.

[0070] The determination of decoupling may be based on data from a position sensing device.The determination of decoupling may be based on data from a linear encoder.

[0071] The safety system can be configured to monitor for excessive linear motion. That is, the safety system can be configured to monitor for linear motion that exceeds the length of the motion or travel path.

[0072] The safety system can be configured to generate an excessive linear motion warning signal upon determining excessive linear motion of the upper member or other linear motion member (eg, linear motion assembly). The excessive linear motion warning signal can be used to shut down the motion transmitting leg.

[0073] The determination of excessive linear motion may be based on data from sensors.

[0074] The determination of excessive linear motion may be switch based.

[0075] The safety system may include at least two switches for determining excessive linear motion. Preferably, the switches are optical switches. Each switch corresponds to a trigger device, such as a flange, a blade, etc., to actuate the switch. Preferably, the trigger device can be configured to interrupt the optical path of the optical switch.

[0076] Each switch can be disposed toward one end of the motion or travel path of the linear motion component (e.g., upper component or linear motion assembly). Each optical switch can be disposed near one end of the second slider element. In these embodiments, the switches can be considered fixed switches because they are in a fixed position relative to the linear motion component.

[0077] Each trigger device can be arranged on the linear motion component, such as the upper component or the linear motion assembly. Preferably, the blade or flange extends from each end of the first slider element. In the embodiment with a fixed switch, since the trigger device moves with the linear motion component, it can be regarded as a movable trigger device.

[0078] In other embodiments, each switch can be arranged on a linear motion component, such as a component or a linear motion assembly. Preferably, each optical switch is arranged at one end of the first slider element. In these embodiments, since these switches move with the linear motion component, they can be regarded as movable switches.

[0079] In embodiments with a movable switch, each trigger device may be disposed toward one end of the motion or travel path of the linear motion component. Preferably, a blade or flange is disposed proximate each end of the second slider element and extends into the path of the movable switch. In these embodiments, since these trigger devices are in a fixed position relative to the moving portion, they may be considered fixed trigger devices.

[0080] At least one of the switches can be arranged on the same side as the motor controller. That is, at least one switch can be close to the motor controller. This reduces the length of the connecting wire.

[0081] Preferably, during normal operation, a component that moves in a straight line (such as an upper component or a linear slide assembly) is limited or constrained to move between two predetermined points. When a component that moves in a straight line moves beyond a predetermined point, excessive linear motion may be considered to have occurred.

[0082] The predetermined point may be set before the motion transfer leg is supplied to the user.

[0083] The switch is positioned so that it is activated only when the component moves beyond a predetermined point. That is, during normal operation of the motion transmitting leg, the switch will not be activated.

[0084] Being able to monitor excessive linear motion ensures that if the upper member were to move beyond the motion or travel path, it can be stopped and subsequently synchronized with the other motion transfer legs in the system. This is beneficial because the safety system can detect problems early, helping to prevent further damage to the legs.

[0085] According to a second aspect of the present invention, there is provided a kit of parts comprising a plurality of motion transmitting legs according to the first aspect of the present invention.

[0086] The kit of parts may also include a central control hub for connecting each motion transmitting leg. The central control hub can synchronize the linear motion of the motion transmitting legs.

[0087] According to a third aspect of the present invention, there is provided a bed retrofitted with a plurality of motion transmitting legs according to the first aspect of the present invention, wherein the upper member of each motion transmitting leg is detachably connected to a bed frame or bed leg.

[0088] According to a fourth aspect of the present invention, there is provided a bed comprising a bed frame and a plurality of motion transmitting legs according to the first aspect of the present invention, the motion transmitting legs being attached around the bed frame.

[0089] According to a fifth aspect of the present invention, there is provided a motion transmission device for transmitting oscillatory or reciprocating linear motion to an object, the motion transmission device comprising:

[0090] Base;

[0091] an upper member movable relative to the base in a motion path, the upper member being adapted to impart oscillatory or reciprocating linear motion to the object; and

[0092] means for defining the path of motion between the base and the upper member (such as an electric motor or other drive means or one or more rails or guides),

[0093] Wherein the upper member is displaceable in a horizontal plane independently of its movement along the movement path, so that at least a portion of the upper member rotates and / or translates relative to the base and the movement path limiting device.

[0094] The upper member may be displaced in any direction within the horizontal plane, such that the upper member rotates and / or translates.

[0095] The upper part may comprise means for displacing the upper part in a horizontal plane.This enables the orientation of the upper part to be changed relative to the base.

[0096] The upper member may include flexible or resilient members to enable displacement, extension or twisting of the upper member in a horizontal plane.

[0097] The upper member may comprise rubber or another elastomeric material.

[0098] Any feature or independently selected combination of features presented in relation to any preceding aspect of the invention may be provided in this fifth aspect of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0099] For a better understanding of the invention and to more clearly show embodiments thereof, reference is now made, by way of example only, to the accompanying drawings, in which:

[0100] Figure 1 shows a perspective view of a first embodiment of a motion transmitting leg according to the first aspect of the present invention;

[0101] Figure 2 Shown without base Figure 1 perspective view of the mid-motion transfer leg;

[0102] Figure 3 Shows Figure 1 and Figure 2 A perspective view of the motion transmitting leg of the invention, better showing its linear axis motor;

[0103] Figure 4 Shows Figures 1 to 3 Cross-sectional view of the mid-motion transfer leg;

[0104] Figure 5 shows a perspective view of a second embodiment of a motion transmitting leg according to the first aspect of the invention;

[0105] Figure 6 Shown without base Figure 5 perspective view of the mid-motion transfer leg;

[0106] Figure 7 Shows Figure 5 and Figure 6 A perspective view of the motion transmitting leg of the invention, better showing its linear axis motor;

[0107] Figure 8 Shows Figures 5 to 7 Cross-sectional view of the mid-motion transfer leg;

[0108] Fig. 9 A perspective view showing the top of the upper member and linear motion assembly in the first and second embodiments;

[0109] Fig.10 A perspective view of the first and second embodiments with a shroud is shown. DETAILED DESCRIPTION

[0110] A first embodiment of a motion transmitting leg (or device) for providing an oscillating or reciprocating linear motion to a bed so as to rock the bed is generally indicated at 10. Figures 1 to 4A second embodiment of a motion transfer leg (or device) is generally indicated at 100. Figures 5 to 8 Similar features in both embodiments will be indicated using the same reference numerals.

[0111] In the first and second embodiments, the motion transmitting leg 10, 100 comprises a rectangular planar base 12 and an upper member 14 movable relative to the base 12. In use, the base 12 is in contact with the floor and the upper member 14 is connected to the bed frame or bed legs to transmit oscillating or reciprocating linear motion to the bed.

[0112] A linear axis motor 16 is provided above the base 12. The linear motor 16 includes a fixing portion 16a and a fixing portion 16a extending along a direction AA (eg, Figure 2 and Figure 6 The movement of the moving portion 16b directly drives the linear motion of the upper member 14. Therefore, it is not necessary to convert the rotary motion of the motor into linear motion to drive the motion of the upper member 14. This reduces the number of parts required for the motion transmitting leg 10, 100 and makes the design simpler and more compact than previous designs.

[0113] Can be Figure 3 The linear axis motor 16 can be seen more clearly in FIG.

[0114] The fixed portion 16a of the linear axis motor 16 is a shaft extending along the longitudinal length of the base 12. The moving portion 16b is a rectangular block with a hole running through its length, wherein the fixed portion 16a passes through the hole. The moving portion 16b includes a coil placed within the block and cylindrically wound around the hole. The fixed portion 16a includes a plurality of magnets arranged along the length of the shaft.

[0115] There is a gap between the fixed part 16a and the moving part 16b. This means that there is no contact or friction between the fixed part 16a and the moving part 16b at any point, especially when the moving part 16b slides along the fixed part 16a. This makes the linear axis motor 16 have high precision, no noise and zero jamming characteristics.

[0116] The length of the moving portion 16b is shorter than that of the fixed portion 16a, so that the moving portion 16b can slide linearly along the fixed portion 16a.

[0117] Each end of the fixed portion 16a, ie each end of the shaft, is connected to a block 18 mounted on the base 12. This allows the linear axis motor 16 to be supported and spaced apart from the base 12.

[0118] The linear motion assembly is connected to and substantially surrounds the moving portion 16 b of the linear axis motor 16 .

[0119] The linear motion assembly includes a carriage 20 and a linear slider assembly.

[0120] The carriage 20 forms the top of the linear motion assembly. The carriage 20 includes a recess that receives approximately half of the moving portion 16 b of the linear axis motor 16 .

[0121] The linear slide assembly includes two sets of first slide elements 22a, 122a and second slide elements 22b, 122b forming two sides of the linear motion assembly. The first set is arranged on one side of the linear axis motor 16 and the second set is arranged on the other side of the linear axis motor 16.

[0122] Each first slide element 22 a , 122 a is in the form of a sliding block and each second slide element 22 b , 122 b is in the form of a shaped guide mounted to the base 12 .

[0123] In the first embodiment, each first slider element 22a includes a groove extending along its length, and the groove is shaped and sized to receive the corresponding second slider element 22b. The top of each first slider element 22a is connected to one end of the carriage 20 and is substantially disposed on the top of the second slider element 22b.

[0124] In the second embodiment, the first slider elements 122a are T-shaped elements. Each first slider element includes a first part and a second part extending perpendicularly from the center of the first part to form the T-shape.

[0125] The second slider elements 122b are U-shaped elements. Each second slider element 122b includes two arms connected together at one end thereof to form a U-shape.

[0126] The outer surface of one of the arms of each U-shaped second slider element 122b abuts the base 12. The second part of the T-shaped first slider element is disposed between the arms of its corresponding second slider element. The first slider element 122a does not abut or contact the base 12.

[0127] A first carrier magnet 24 is arranged in a hole at the end of the first part of each T-shaped first slider element 122a. Figure 7 . A second carrier magnet 26 is disposed on each face of the second part of each T-shaped first slider element 122a. A base magnet 28 is disposed on the inner face of each arm of each U-shaped second slider element 122b. This allows the first carriage magnet 24 to be disposed on the lateral side of its corresponding base magnet 28 and helps maintain the linear motion of the linear motion assembly. The second carriage magnet 26 and the base magnet 28 together allow the weight of the bed to be borne by the motion transfer leg 100.

[0128] There is a gap between the first and second carriage magnets 24, 26 and the base magnet 28. The gap between the first and second slider elements 122a, 122b means that there is no contact or friction between the first and second slider elements 122a, 122b. This helps prevent wear on the linear motion assembly and does not require maintenance or servicing.

[0129] The magnet in Figure 7 The magnets can be permanent magnets and / or electromagnets.

[0130] In both embodiments, the linear slide assembly supports the carriage 20 and ensures that during use, the weight of the bed is transferred to the base 12 of the motion transmitting leg. This enables the motion transmitting legs 10, 100 to support heavier beds as each leg can bear more weight.

[0131] The linear slide assembly extends in a direction parallel to the fixed portion 16 a of the linear axis motor 16 . The linear motion of the linear slide assembly is parallel to the linear motion of the linear axis motor 16 .

[0132] The upper member 14 is connected to the carriage 20. The upper member 14 is a rectangular planar member located on the top of the carriage 20. The upper member 14 covers substantially the entire top surface of the carriage 20. The linear motion assembly causes the upper member 14 to perform linear motion along the length of the fixed portion 16a of the linear axis motor 16.

[0133] A flexible or resilient member or layer 30, such as a rubber layer, is provided between the upper member 14 and the carriage 20 of the linear slide assembly. Fig. 9 Be able to see more clearly.

[0134] The flexible or resilient member 30 is connected to the upper member 14 and the carriage 20 using an adhesive. However, other connection methods, such as galvanizing, may also be used. The flexible or resilient layer 30 allows the upper member to rotate and translate relative to the carriage 20.

[0135] This is useful, for example, when the motion transmitting leg 10, 100 is attached to the bed together with other motion transmitting legs. The rotation of the upper part 14 in the BB direction and the translation in the CC and DD directions means that all the motion transmitting legs attached to the bed do not have to be perfectly aligned with each other. This is because the upper part 14 can be moved slightly to align with the upper parts of the other motion transmitting legs.

[0136] Fastening means 32, ie screws, extend through the upper member 14, the flexible or resilient member 30 and the carriage 20 to further secure them together.

[0137] A shield 34 is provided to enclose components of the motion transmitting legs 10, 100, such as Fig.10The shield 34 is connected to the upper member 14 by fasteners such as bolts or screws, which pass through holes in the upper member 14.

[0138] In this embodiment, the linear encoder 36 is mounted to the base 12 and is placed in the space between the base 12 and the linear axis motor 16. However, in other embodiments, the linear encoder 36 can be placed anywhere between the fixed (e.g., base) and moving parts (e.g., upper member, linear motion assembly) of the motion transmitting leg 10, 100, for example.

[0139] A motor controller (not shown) is connected to the linear encoder 36. The motor controller controls the speed of the linear axis motor 16 based on the position data of the linear encoder 36. The motor controller also controls the speed control hub of the motor 16 based on, for example, a desired motion or position path received from the control hub.

[0140] When multiple motion transmitting legs are retrofitted to a standard bed, the bed will oscillate or reciprocate in a horizontal plane, ie, in a direction generally parallel to the floor.

[0141] A central hub (not shown) may be provided to control and provide power to the motion transmitting legs. The central hub may be connected to each motion transmitting leg by cables. The cables provide a path for data communication and power.

[0142] The central hub receives data and / or signals from each motion transfer leg. The central hub may send commands, signals, data and / or information to each motion transfer leg. The central control hub may be configured to synchronize the motion of the legs.

[0143] The safety system is configured and arranged to determine unexpected operation of the motion transmitting leg 10, 100. For example, the safety system can be used to determine whether there is a decoupling, either complete or partial, between a component and the linear motion of the linear axis motor 16. For example, decoupling may occur when the displacement or motion of the linear axis motor is blocked by an obstacle, or when the motor burns out, or when a connecting line is disconnected.

[0144] If decoupling is determined, the motor controller generates a warning signal that is transmitted to the central hub. The central control hub can then generate a shutdown signal that is transmitted to all motion transmitting legs 10, 100.

[0145] In some embodiments, the safety system uses data from the linear encoder 36 to determine if a decoupling exists. In other embodiments, the safety system uses data from the linear encoder 36 plus a monitored electrical value of the linear axis motor 16, such as current.

[0146] The safety system is configured to determine excessive linear motion. That is, the safety system determines that the upper component 14 has moved beyond one end of its defined motion or travel path length. The safety system can use the linear motion of other components such as the linear motion assembly or the shield 34 to infer the motion of the upper component 14.

[0147] The safety system includes two optical switches 38, 138 connected to the motor controller. Each optical switch 38, 138 is arranged toward one end of the linear slider assembly, specifically the second slider element 22b, 122b. Each optical switch 38, 138 has a switch gate composed of two columns, and an optical path is provided between the columns.

[0148] A blade 40, 140 or similar switch triggering device is provided at either end of the first slider element 22a, 122a. Each blade 40, 140 extends from the first slider element 22a, 122a toward the optical switch 38, 138. The blade 40, 140 actuates the optical switch 38, 138 by interrupting the optical path in the switch door.

[0149] During normal operation of the motion transmitting leg 10 , 100 , the blade 40 , 140 does not actuate the optical switch 38 , 138 .

[0150] If the optical switch 38, 138 is actuated, the motor controller will generate a warning signal that is transmitted to the central hub. The central control hub can then generate a shutdown signal that is transmitted to all motion transmitting legs 10, 100.

[0151] The optical switch 38, 138 may also be used in a method of calibrating the motion transmitting leg 10, 100. The method will now be described with reference to the above-described embodiment, but it is also applicable to other types of motion transmitting legs.

[0152] To calibrate the motion transfer legs 10, 100 and determine the maximum range of possible linear motion, the linear axis motor 16 drives the linear motion assembly until the blade 40, 140 actuates the optical switch 38, 138. Actuation of the optical switch 38, 138 indicates one end of the linear motion path. The motor controller records position data indicating one end of the motion path.

[0153] Once one end is recorded, the motion transfer leg 10, 100 goes through the same steps but reverses the direction of the linear axis motor 16 to determine the other end of the linear path.

[0154] Once both ends are recorded, the range of possible linear motion, i.e., maximum motion or travel path length, is determined and the linear motion assembly is moved back toward a center position, i.e., approximately equal distance between the two ends.

[0155] In this embodiment, the optical switch 38, 138 should not be actuated during normal operation of the motion transmitting leg 10, 100. This means that the actual motion or travel path length must be less than the maximum motion or travel path length so that the blade 40, 140 does not trigger the optical switch 38, 138.

[0156] In this embodiment, the actual moving path length is 4 mm shorter than the maximum moving path length, that is, there is a 2 mm margin at each end.

[0157] The motion transfer legs can be provided as pre-calibrated units. That is, the end user does not have to perform any calibration before installing / using the legs.

[0158] Although both the first and second embodiments include linear axis motors, other types of motors or motion path defining devices may be used to drive or cause or allow linear motion of the upper member.

[0159] The embodiments described above are provided by way of example only and those skilled in the art will appreciate that various changes and modifications may be made without departing from the scope of the present invention as defined in the appended claims.

Claims

1. A motion transmitting leg for applying oscillation or reciprocating linear motion to a bed to make the bed rock, the motion transmitting leg comprising: A base; an upper member movable relative to the base, for transmitting the oscillating or reciprocating linear motion; a linear axis motor for driving the upper member to move linearly, the linear axis motor comprising a fixed portion and a movable portion spaced apart from each other, the movable portion being movable linearly relative to the fixed portion; a position sensing device for determining the position of the linear axis motor or the position of the upper member; and a motor controller for controlling the linear axis motor based on data from the position sensing device.

2. The motion transmitting leg of claim 1, wherein the upper member is disposed above or attached to the linear axis motor.

3. The motion transmitting leg according to claim 1 or 2, wherein the linear motion path of the upper member extends along the length of the fixed portion of the linear axis motor.

4. A motion transferring leg according to any preceding claim, wherein the upper member is adapted to be displaced in a horizontal plane so as to enable rotation and translation of the upper member relative to the base.

5. The motion transferring leg of claim 4, wherein the upper member includes a flexible or elastic member to enable displacement of the upper member.

6. The motion transmitting leg according to claim 5, wherein the entire upper member is a flexible or elastic member.

7. The motion transmitting leg according to any of the preceding claims, further comprising a linear motion assembly disposed between and connected to the moving portion of the linear axis motor and the upper member.

8. The motion transferring leg of claim 7, wherein the flexible or resilient member is the portion of the upper member that is connected to the linear motion assembly.

9. A motion transferring leg according to claim 7 or 8, wherein fastening means are provided to secure the linear motion assembly and the upper member together.

10. The motion transmitting leg according to any one of claims 7 to 9, wherein the linear motion assembly comprises a recess for accommodating at least a part of the moving portion of the linear axis motor.

11. A motion transfer leg according to any one of claims 7 to 10, wherein the linear motion assembly comprises a carriage and a linear slider assembly, the linear slider assembly comprising a first slider element connected to each side of the carriage and a second slider element connected to the base and arranged between the linear axis motor and each of the first slider elements.

12. The motion transmitting leg according to claim 11, wherein each first slider element is substantially T-shaped, having a first part and a second part extending vertically from the center of the first part, each second slider element is substantially U-shaped and has two arms connected together, and the second part of the first slider element is arranged between the arms of the second slider element.

13. The motion transmitting leg according to any one of claims 7 to 12, wherein a group of magnets or electromagnets are provided on the linear motion assembly to bear the weight applied to the upper member and maintain the linear motion of the linear motion assembly.

14. A motion transferring leg according to claim 13 when dependent on claim 11, wherein each first slider element is provided with at least one first carriage magnet and at least one second carriage magnet, and each second slider element is provided with at least one base magnet.

15. The motion transfer leg according to claim 14, wherein the at least one first carriage magnet is disposed on a lateral side of the at least one base magnet, and the at least one second carriage magnet is disposed above or below the at least one base magnet.

16. The motion transferring leg of claim 14 or 15, wherein the at least one first carriage magnet and the at least one second carriage magnet are spaced apart from the at least one base magnet.

17. A motion transferring leg according to any preceding claim, wherein the position sensing device is mounted beneath the linear axis motor.

18. A kit of parts comprising a plurality of motion transmitting legs according to any one of claims 1 to 17.

19. The kit of parts of claim 18, further comprising a central control hub connected to each motion transmitting leg, said central control hub synchronizing said linear motion of said motion transmitting legs.

20. A bed retrofitted with a plurality of motion transmitting legs according to any one of claims 1 to 17, wherein the upper part of each motion transmitting leg is detachably connected to a bed frame or bed leg.

21. A bed comprising a bed frame and a plurality of motion transmitting legs according to any one of claims 1 to 17, the motion transmitting legs being attached around the periphery of the bed frame.

22. A motion transmission device for imparting oscillation or reciprocating linear motion to an object, the motion transmission device comprising: Pedestal; an upper member movable relative to the base on a motion path, the upper member being used to impart the oscillating or reciprocating linear motion to the object; as well as a movement path defining means between the base and the upper member, Wherein the upper member is displaceable in a horizontal plane independently of its movement along the movement path, so that at least a portion of the upper member rotates and / or translates relative to the base and the movement path defining means.

23. The motion transfer device of claim 22, wherein the upper member includes means for displacing the upper member within the horizontal plane.

24. The motion transfer device according to claim 22 or 23, wherein the upper member comprises a flexible or elastic member to enable the upper member to be displaced, stretched or twisted in a horizontal plane.

25. A motion transfer device according to any one of claims 22 to 24, wherein the upper member comprises rubber or another elastomeric material.

Images