WO2022211742A1

WO2022211742A1 - A mechanism for separating rotary and linear movement of a guide shaft and a device for measuring the position of the guide shaft, comprising said mechanism

Info

Publication number: WO2022211742A1
Application number: PCT/SI2022/050008
Authority: WO
Inventors: Miran DOMAJNKO
Original assignee: Rls Merilna Tehnika D.O.O.
Priority date: 2021-03-30
Filing date: 2022-03-03
Publication date: 2022-10-06
Also published as: SI26183A

Abstract

The body for separating the rotational and linear motion solves the problem of separating the rotational and linear motion of the guide shaft (3). According to the invention, the body includes a guide shaft (3), a static part (2) of the body and a rotary part (1) of the body. The movement of the guide shaft (3) relating to the static part (2) is enabled by the first supports (7). The transmission of the rotation of the guide shaft (3) is ensured with the rotation transmission attachment (12), which is attached to the guide shaft (3). With the help of second supports (13) inside the rotation transmission attachment (12) for transmitting rotation, and one or more guides (11), the rotation transmission attachment (12) transfers rotation to the rotary part (1) of the body, which is, via a connecting element (10) with one or more third supports (14), separated from the static part (2) of the body. The rotation of the guide shaft (3) is transmitted via the rotation transmission attachment (12) to the rotary part (1) of the body, using the guides (11) and the connecting element (10) to which the guides (11) are fixed. The device for simultaneously measuring rotary and linear movement of the guide shaft (3) includes said body and position encoders, which are mounted on the body. The body further includes an encoder readhead (9) for measuring rotation and an encoder readhead (8) for measuring linear movement, both mounted in the static part (2) of the body, an encoder scale (B) mounted in the rotary part (1) of the body for measuring rotation, and an encoder scale (D) integrated in the guide shaft (3) for measuring the linear movement.

Description

A MECHANISM FOR SEPARATING ROTARY AND LINEAR MOVEMENT OF A GUIDE SHAFT AND A DEVICE FOR MEASURING THE POSITION OF THE GUIDE SHAFT, COMPRISING SAID MECHANISM

The invention relates to a body for separating rotary and linear movement of the guide shaft and to a device for measuring the position of the guide shaft, which includes the above-mentioned body. In the context of this application the term "guide shaft" refers to any element for transmitting rotational and / or auxiliary linear motion, preferentially a moving axle or a shaft. The body is made of a static part, a rotary part, and a guide shaft. The guide shaft moves linearly and / or rotationally through the static part of the body, wherein the construction of the body allows separate but synchronous observation of the rotation and translation of the guide shaft at a given moment.

The device for measuring the position of the guide shaft includes the said body and at least a rotary encoder mounted on the body for measuring the rotation of the guide shaft. In this case, the body further includes an encoder readhead for measuring rotation, located in the static part of the body, and an encoder scale for determining the rotation, located in the rotary part of the body. However, the device may additionally include a linear encoder, which is also mounted on the body, for measuring the linear movement of the guide shaft. In this case, the body further includes an encoder readhead for measuring the linear movement, located in the static part of the body, and an encoder scale for determining the linear movement, integrated in the guide shaft. Preferably, the device includes both encoders for simultaneously measuring linear movement and rotation of the guide shaft. Therefore, the device allows either linear movement measurement or rotary movement measurement or linear and rotary movement measurement of the guide shaft at a given moment via both position encoders.

The technical problem, solved by the invention, is such a body construction that allows simultaneous free linear movement of the guide shaft and / or rotation of the guide shaft through the static part of the body and at the same time ensures rotation of the rotary part of the body together with the guide shaft. The device, according to the invention, with appropriately placed encoder readheads and encoder scales in the body via both position encoders, enables either separate measurement of rotary or linear movement, or simultaneous measurement of rotary and linear movement of the guide shaft.

If the guide shaft rotates and moves linearly, the rotary part of the body rotates relative to the static part of the body by the same angle as the rotating guide shaft, which allows measuring the rotation through the rotary encoder. At the same time, the guide shaft moves linearly with respect to the static part of the body, which allows measuring the linear movement via the linear encoder. The known solutions are mainly based on the installation of a rotary part on a mobile station, which has the disadvantage of space complexity, speed limits, clearance, and the addition of errors.

There are not many known solutions in such version, they all focus on actuators (or at least derive from this area) and not position encoders and are consequently different. Existing solutions are based primarily on the installation of a rotary encoder or components for observing the rotation to a mobile station, under which or at which the linear movement is measured separately at the same time.

The disadvantage is the spatial complexity of the design and the resulting clearance, and at the same time such solutions have speed limitations and problems with cables. There are no stationary bodies on the market that can be used for the heads of both encoders (for rotary and linear movement). Patent application no. US20090302832A1 describes a measuring system for detecting roto-linear movements. It is based on a very complex and specific separation of rotation and translation. Patent no. CN102171914B and patent application no. WO2011141236 describe roto-linear actuators and motors. Various research papers have been published dealing with roto-linear motors with two degrees of freedom, for example L. Xie, J. Si, Y. Hu and Z. & Wang, "Overview of 2-Degree-of-Freedom Rotary-Linear , "IEEE TRANSACTIONS ON MAGNETICS, vol. IV, no. vol. 55, April 4, 2019 in J. F. Pan, Z. Yu and N. C. Cheung, "Performance Analysis and Decoupling Control of an Integrated Rotary - Linear Machine With Coupled Magnetic Paths," IEEE TRANSACTIONS ON MAGNETICS, vol. II, no. vol. 50, 2014. Most often, such movements are performed with rotary motors attached to linear motors. Motion accuracy is limited, as there is always some clearance and addition of errors, so for more demanding applications, a single-drive version would be more appropriate. The development of a single (rotary- linear) motor that will be commercially useful presents potential opportunities for the use of the proposed body to analyse these movements. Very precise linear movement of the parts is usually done via a ball screw spindle. Much research has already been done in the field of changing rotational motion to linear (eg Y. Hojjat and MM Agheli, "A comprehensive study on the capabilities and limitations of roller - screwwith emphasis on slip tendency," Mechanism and Machine Theory, Vol. 44, No. Issue 10, pp. 1887-1899, 2009), which addresses the potential and many limitations of this transition. Patent no. US3777578 deals and solves the mentioned problem of transition with the help of bearings and friction. According to the invention, described technical problem is solved with a body for separating rotary and linear movement and with a device for measuring position, i.e., linear and / or rotary movement, which includes said body.

To transfer the rotation of the guide shaft to the rotary part of the body, the body is made with one or more additional guides. They can be a variety of guides (rail, round, telescopic, tubular), but preferably the guides are round linear guides. The guide (or more, preferably two or three) rotates due to the rotation transmission attachment, which is fixed to the end or to any position of the guide shaft, but at the same time the rotation transmission attachment can travel linearly along the guide or guides. The rotation transmission attachment is fixed to the guide shaft and has suitable mounting locations for the installation of one or more supports, preferably linear bearings, through which the guides are connected to the guide shaft. As the guide shaft moves, the built-in linear bearings also move and / or rotate with it. The guides on which the linear bearings run are not affected by the linear movement of these bearings attached to the rotation transmission attachment. The rotation transmission attachment (with the mentioned bearings) slides freely on the guides. However, if the guide shaft rotates, it also rotates the rotation transmission attachment and consequently the linear bearings, which then rotate the guides running through the linear bearings. Since the guides are fixed to the connecting element, connecting the static part of the body with the rotary part, the rotation of the guide shaft is transmitted via the guides to the connecting element of the body, allowing the rotation of rotary part of the body relative to the static part of the body.

The invention is described in more detail below with a preferred embodiment and presented in the illustrative figures fig. 1 body according to the invention in axonometric projection and with a section view fig. 2 version of the body with extended guide shaft fig. 3 longitudinal section view of the body with built-in encoder readheads and encoder scales along the line Z-Z and enlarged part of the area marked with P fig. 4 Embodiment of a body with a fixed support. According to the invention the body includes an element for transmitting rotational and / or linear movement, i.e., the guide shaft 3, the static part 2 of the body and the rotary part 1 of the body.

The static part 2 of the body includes a housing 4 with a through hole for receiving the guide shaft 3. The housing 4 can be shaped as desired. Preferably, the housing 4 is cylindrical in shape and in one embodiment of the invention it is provided on its lower side with a separate connecting element 5 and on its upper side with a separate cover 6, with openings for receiving the guide shaft 3. In another embodiment of the invention, the housing 4 can be on its own; the upper side is made with a separate cover 6 with openings for receiving the guide shaft 3. In yet another embodiment of the invention, the housing 4 can be made as a single cylindrical element with a through hole for receiving the guide shaft 3. The guide shaft 3 is connected to the housing 4 via at least one first supports 7, to allow linear movement of the guide shaft 3 and to allow rotation of the guide shaft 3 relative to the housing 4. There may be more first supports 7. Preferably, the connection is made with two first supports 7, which are preferably sliding bearings. Housing 4 preferably also includes openings E for receiving electrical wires.

The rotary part 1 of the body includes a connecting element 10, one or more guides 11 fixedly attached to the connecting element 10, and a rotation transfer attachment 12 for transmitting rotation, i.e., rotation of the guide shaft 3 to the guide / guides 11. The rotation transmission attachment 12 for transmitting rotation is fixed to guide shaft 3 and has suitable mounting locations for one or more second supports 13, through which the guides 11 are connected to the guide shaft 3 to allow the rotation transmission attachment 12 to slide along the guides 11 and to transmit the rotational movement of the guide shaft 3 to the guides 11 and then via guides 11 to the connecting element 10. The mounting locations are preferably holes into which second supports 13 are inserted. Preferably, the second supports 13 are linear bearings, which are preferably sliding or ball bearings.

The rotary part 1 of the body is connected to the static part 2 of the body via the connecting element 10. The connecting element 10 can be connected to the separate connecting element 5 of the housing 4 of the static part 2 of the body when the housing 4 is made with the connecting element 5 and the separate cover 6, or to the lower part of the housing 4 of the static part 2 of the body when the housing 4 is made as a single element and when the housing 4 is provided with a separate cover 6. From here on, in the context of this application, the term "connection of connecting element 10 to the housing 4" includes both variants, thus connecting connection element 10 to separate connecting element 5 of the housing 4 when the housing 4 is made with separate connecting element 5 and cover 6, as well as the connection of the connecting element 10 directly to the lower part of the housing 4, when the housing 4 is made as a single element or when the housing 4 is made with a separate cover 6. The connection of the connecting element 10 to the housing 4 is made via at least one third support 14, preferably via two supports 14, where the rotation of the guide shaft 3 via the guides 11 is transferred to the connecting element 10, which allows the rotation of the rotary part 1 of the body with respect to the static part 2 of the body. With the built-in encoder readhead 9 for measuring rotation, located in the static part 2 of the body, and with the encoder scale B for measuring the rotation, which is attached to the connecting element 10, it is possible to measure the rotation. There may be more third supports 14 to improve the accuracy and precision of the rotation measurements. Third supports 14 are preferably radial ball bearings. When the guide shaft 3 is rotated, one or more guides 11 are rotated simultaneously via the rotation transmission attachment 12, and so via guides 11, fixedly connected to the connecting element 10, the connecting element 10 also rotates.

Optionally, the body may include a protection 16 mounted on the guides 11 at the far end of the guides 11 from the housing 4, to secure the free ends of the guides 11 together in terms of rigidity and torsional stress resistance.

Optionally, the body may include a rigid cover 15 that is preferably cylindrical in shape and surrounds the guides 11. The purpose of the rigid cover 15 is to mechanically protect the guides 11 and the guide shaft 3 in the area of guides 11 while contributing to system rigidity and torsional stress resistance. The rigid cover 15 is rotary in some embodiments of the invention, and is fixed to the connecting element 10, to which the guides 11 are also fixed, so that the rigid cover 15 is connected to the housing 4 in a rotating relation via the connecting element 10.

In another embodiment of the invention, the rigid cover 15 is fixed; the rigid cover 15 is fixed to the static part 2 of the body, and the guides 11 rotate within the rigid cover 15. Optionally, the body may also include a fixed support 17 at the far end of the guides 11, away from the housing 4, which serves for the mechanical stability of the guides 11 and consequently of the entire body. The bearing arrangement of the guides 11 at the fixed support 17 is made in the case of fixed rigid cover 15 via the protection 16, and in the case of the rotating rigid cover 15 via the protection 16 or via the rotating rigid cover 15. The bearing arrangement is made with at least one bearing 18, preferably mounted so that the outer part of the bearing 18 is attached to the fixed rigid cover 15 and the inner part of the bearing 18 is attached to the protection 16, wherein in the case of the rotating rigid cover 15, the bearing 18 is preferably mounted so that the outer part of the bearing 18 is fixed to the fixed support 17 and the inner part of the bearing 18 is attached to the protection 16 or to the rotating rigid cover 15. Preferably, the bearing 18 is a rotary bearing.

In one embodiment of the invention, the body comprises two rigid covers 15, fixed and rotary one, wherein the rotary one is located inside the fixed one.

In one embodiment of the invention, the guide shaft 3 can be extended so that it extends from the rotary part 1 of the body, as shown in Figure 2. In this case, the guide shaft 3 can be operated on its own, which further expands the range of possibilities for the use of invention. If the guide shaft 3 extends from the support on the other side, we can also influence the movement of the guide shaft 3 on the other side, which is further explained in the preferred embodiment of the invention.

Figure 2 also shows the preferred method of mounting the body; showing the mounting surface MS. Other suitable surfaces can also be used to mount the body.

Elimination of hysteresis and improvement of accuracy is solved, if necessary, by eliminating clearance in second supports 13 by inserting press fit plungers, which press one or more guides 11 against the second support 13, i.e., linear bearings. In this way, when the guide shaft 3 is rotated, the rotation transmission attachment 12 rotates simultaneously with guide shaft 3, and consequently the entire rotary part 1 of the body; they all rotate at the same time and with little or no hysteresis. As already mentioned before, the device for measuring the position includes aforementioned body and at least a rotary encoder for measuring the rotation of the guide shaft 3, which is mounted on the body. In this case, the body further includes encoder readhead 9 for measuring rotation, located in the static part 2 of the body, and encoder scale B for measuring rotation, which is attached to the connecting element 10.

The encoder readhead 9 for measuring rotation is installed in the static part 2 of the body so that it is possible to measure rotation of the encoder scale B on the rotary part 1 of the body, thus determining rotation of the guide shaft 3. Preferably, the encoder readhead 9 for rotation measurement is positioned on the side where the static part 2 of the body is connected to the rotary part 1 of the body. The encoder readhead 9 for measuring rotation is preferably attached to the connecting element 5 of the housing 4 of the static part 2 of the body when the housing 4 is made with a connecting element 5 and separate cover 6 or to the lower part of the housing 4 of the static part 2 of the body when the housing 4 is made as a single element, when the housing 4 is made with a separate cover 6.

The encoder scale B for measuring rotation is attached to the connecting element 10 and positioned so that it is possible to measure rotation with the encoder readhead 9 for measuring rotation. The encoder scale B for measuring rotation can be performed in known ways that allow rotation measurement, for example the encoder scale B can be optical, inductive, capacitive, magnetic, ... Preferably, the encoder scale B is in the form of a magnetic ring.

In a preferred embodiment of the invention, the encoder scale B is in the form of a magnetic ring, and it is placed at the end of the connecting element 10, and the encoder readhead 9 is placed in the static part 2 of the body so that it lies opposite to the magnetic ring. As the guide shaft 3 rotates, the rotational movement of the guide shaft 3 is transmitted via the rotation transmission attachment 12 to the guides 11, fixedly attached to the connecting element 10, whereby the connecting element 10 and thus the magnetic ring located at the end of the connecting element 10 rotate, and the encoder readhead 9 measures the rotation of the guide shaft 3. In the case where the device for measuring the position, i.e., linear and rotary movement, also includes a linear encoder for determining the linear movement of the guide shaft 3 mounted on the body, the body further includes an encoder readhead 8 for measuring linear movement located in the static part 2 of the body, and encoder scale D for measuring linear movement integrated in the guide shaft 3. Encoder scale D for measuring linear movement can be performed in known ways that allow linear movement measurements, for example encoder scale D can be optical, inductive, capacitive, magnetic, ... Preferably, the encoder scale D is magnetic.

When the guide shaft 3 moves linearly, the encoder scale D integrated in the guide shaft 3 moves past the encoder readhead 8, which measures the linear movement of the guide shaft 3.

The advantage of the presented body and device construction, according to the invention, is that it provides points A and C, where simultaneous observation and measurement of rotation of the moving guide shaft 3 from a fixed point is possible, and observation and measurement of linear movement of the same guide shaft 3 from another fixed point is also possible when the guide shaft 3 is also encoder scale, i.e., the encoder scale is integrated in the guide shaft 3. Without the use of the defined body, the static part of the rotary encoder with the rotary encoder readhead must travel linearly together with the measuring rod or a collision / displacement occurs with simultaneous linear movement.

According to the invention, the body enables mounting of the encoder scale B of the rotary encoder on the rotary part 1 of the body and mounting of the encoder readheads 8, 9 of both encoders, i.e. rotary and linear, on the static part 2 of the body. The encoder scale D of the linear encoder is integrated in the guide shaft 3. When using a device for simultaneous measurement of rotation and linear movement, the linear movement is measured in area C by means of an encoder readhead 8 mounted in the static part 2 of the body and with an encoder scale D on the guide shaft 3, and rotation is measured in area A by means of encoder readhead 9 mounted on the static part 2 of the body and an encoder scale B attached to the connecting element 10.

If necessary, the entire device can be packed in a box or other housing so that everything is covered for the user, except the guide shaft 3, which extends from the housing at one or both ends. Preferred embodiment

One of the possible uses of this body is in medical devices, for example for ultrasound examination of the prostate, where it is crucial that the data on linear and angular displacement are captured synchronously, i.e., at the same time. In this case, according to the invention, the body is included in a device which, in addition to the body, includes a rotary encoder and a linear encoder, and an additional electronic circuit for capturing and combining electrical signals from both encoders and transmitting them together to the user.

A mechanical and a communication solution is needed to combine rotary and linear measurements. In addition to the electronic circuit that captures and combines the electrical signals from both position encoders, it is necessary to enable the measuring rod, i.e., the guide shaft 3, both linear and rotary movements . Guide shaft 3 should also rotate the rotation part 1 of the body to determine the rotation.

Two mounting points for the rotary encoder and two mounting points for the linear encoder should be provided. Each encoder needs one stationary and one (together with the guide shaft 3) moving (rotating or linearly moving) point.

According to the invention, the body enables described separation of linear and rotary movement. Each movement is then observed and measured with the help of individual position encoder / sensor. The rotary encoder consists of a magnetic scale, i.e., an encoder scale B, which is attached to the rotary part 1 of the body, and an encoder readhead 9, which is attached to the static part 2 of the body. On the static part 2 of the body there is also an encoder readhead 8 for measuring the linear movement, which, together with the magnetic scale, i.e., the encoder scale D, which is integrated in the guide shaft 3, assembles a position encoder.

Assuming the embodiment of the invention as shown in Figure 2, the left end of the guide shaft 3 can be grabbed by hand and the ultrasonic head is attached to the right end of the guide shaft 3. The intended preferred mounting surface is fixed stationary. We can move the guide shaft 3 in and out by hand and rotate it simultaneously or separately if desired (by hand).

Meanwhile at position C, we observe linear movement by means of encoder readhead 8 and integrated encoder scale D of the linear encoder, and at position A, rotation by means of encoder readhead 9 and encoder scale B of the encoder. Together with the previously mentioned electronic circuit for combining signals and two encoders (one for rotation and one for linear movement), we will be able to synchronously obtain data on changes in both movements and send them to the user as a whole.

The innovation and advantage of this invention is the possibility of spatially undemanding design without trolleys and larger guides, which is especially important in other applications with higher movement speeds. At the same time, the small size of the device allows easy access and prevents the addition of errors. We can observe both rotary and linear movement synchronously, in practically the same place, and we are not hindered by cables and other electrical connections when rotating the guide shaft 3.

The device can be very easily integrated into a variety of closed-loop systems and thus allows us to observe both parameters at the same time, which gives us a better and faster ability to respond.

Claims

Patent claims

1. A body for separating rotary and linear motion of a guide shaft (3), wherein the body comprises:

- guide shaft (3);

- a static part (2) of the body, including a housing (4) with a through hole for receiving the guide shaft (3), wherein the guide shaft (3) is connected to the housing (4) via at least one first support (7) for allowing linear movement of the guide shaft (3) and for allowing the guide shaft (3) to rotate relative to the housing (4) and

- a rotary part (1) of the body, comprising a connecting element (10), one or more guides (11) fixedly attached to the connecting element (10), and a rotation transmission attachment (12) for transmitting the rotation of the guide shaft (3) to the guides (11), wherein the rotation transmission attachment (12) is fixed to the guide shaft (3) and has mounting locations for one or more second supports (13) through which the guides (11) are connected to the guide shaft (3) for enabling sliding of the rotation transmission attachment (12) along the guides (11) and for transmitting the rotary movement of the guide shaft (3) to the guides (11) and wherein the rotary part (1) is connected to the static part (2) via the connecting element (10) and the connection is made via at least one third support (14) for transmitting the rotation of the guide shaft (3) via the rotation transmission attachment (12) for transmitting the rotation, and via the guides (11) to the connecting element (10) and thus for allowing the rotation of the rotary part (1) of the body relative to the static part (2) of the body.

2. The body according to claim 1, wherein the housing (4) is cylindrical in shape and is made with a separate connecting element (5) on its lower side, and with a separate cover (6) on its upper side, or the housing (4) is made with the separate cover (6) on its upper side or the housing (4) is made as a single element of cylindrical shape and the guide shaft (3) is connected to the housing (4) via two first supports (7), which are sliding bearings.

3. The body according to claims 1 and 2, wherein the second supports (13) are linear bearings, which are preferably plain or ball bearings.

4. The body according to any preceding claim, wherein the connection of the connecting element (10) with the static part (2) of the body is made via preferably two third supports (14), which are radial ball bearings.

5. The body according to any preceding claim, wherein the rotary part (1) of the body includes one, two or three guides (11), which are preferably round type linear guides (11).

6. The body according to any preceding claim, wherein the body further comprises a protection (16) mounted on the guides (11) at the end of the guides (11) at the far end of the housing (4), for fixing the free ends of the guides (11) in terms of rigidity and resistance to torsional stresses.

7. The body according to any preceding claim, wherein the body further comprises a rigid cover (15) which is preferably cylindrical in shape and surrounds the guides (11) for improving system rigidity, for increasing torsional stress resistance and for mechanical protection of guides (11) and guide shaft (3) in the area of the guides (11), wherein the rigid cover (15) is rotary, and is fixed to the connecting element (10), or the rigid cover (15) is fixed, and is fixed to the static part (2)of the body.

8. The body according to any preceding claim, wherein the body further comprises a fixed support (17) at the far end of the guides (11), for mechanical stabilization of the guides (11) and consequently for the support of the entire body, wherein the bearing arrangement of guide / guides (11) in the area of the fixed support (17) in the case of fixed rigid cover (15) is made through the protection (16), and in the case of rotary rigid cover (15) is made through the protection (16) or through the rotary rigid cover (15) and bearing arrangement is made with at least one bearing (18), which is in the case of fixed rigid cover (15) preferably mounted so that the outer part of the bearing (18) is attached to the fixed rigid cover (15) and the inner part of the bearing (18) is attached to the protection (16), and in the case of a rotary rigid cover (15), the bearing (18) is preferably arranged so that the outer part of the bearing (18) is attached to the fixed support (17) and the inner part of the bearing (18) is attached to the protection (16) or the rotary rigid cover (15).

9. The body according to any preceding claim, wherein the guide shaft (3) is elongated and extends from the rotary part (1) of the support.

10. The body according to any preceding claim, wherein a clearance in the second supports (13) is eliminated by inserting press fit plungers which press the guides (11) against the second support (13) for eliminating hysteresis and for improving accuracy.

11. The body according to any preceding claim, wherein the housing (4) further includes openings (E) for receiving electrical connections / wires.

12. A device for measuring position of the guide shaft (3), including a body according to any one of claims 1 to 11, wherein said device includes a rotary encoder for measuring rotation of the guide shaft (3) mounted on the body, wherein the body further includes an encoder readhead (9) located in the static part (2) of the body on the side where the static part (2) of the body is connected to the rotary part (1) of the body for measuring rotation, and an encoder scale (B) attached to connecting element (10) for measuring rotation.

13. The device according to claim 12, wherein the encoder scale (B) can be optical, inductive, capacitive or magnetic and is mounted on the end of the connecting element (10), preferably the encoder scale (B) is in the form of a magnetic ring.

14. The device according to any one of claims 12 to 13, wherein the device further comprises a linear encoder for measuring the linear movement of the guide shaft (3) mounted on the body, the body further including an encoder readhead (8) located in the static part (2) of the body for measuring linear movement, and an encoder scale (D) integrated in the guide shaft (3) for measuring linear movement, wherein the encoder scale (D) is optical, inductive, capacitive or magnetic, preferably encoder scale (D) is magnetic.

15. The device according to any one of claims 12 to 14, wherein the device further comprises an electronic circuit for receiving and combining electrical signals from both encoders and for transmitting the signals to the user, wherein the electronic circuit is in the housing (4) of the static part (2) of the body.