EP3232295B1

EP3232295B1 - A control lever for precise operation

Info

Publication number: EP3232295B1
Application number: EP17151342.7A
Authority: EP
Inventors: Levent Erkocak
Original assignee: Makersan Makina Otomotiv Sanayi Ticaret AS
Current assignee: Makersan Makina Otomotiv Sanayi Ticaret AS
Priority date: 2016-04-13
Filing date: 2017-01-13
Publication date: 2023-08-23
Anticipated expiration: 2037-01-13
Also published as: EP3232295A2; EP3232295A3; TR201604770U

Description

Technical Field of Invention

The present invention relates to an industrial control lever and more particularly to a reliable control lever with increased precision suitable to be used in industry, agriculture, construction equipment, marine vessels, aviation and similar fields of operation.

State of the Art

Currently, control levers, also called as joysticks, are often used in industrial field in order to control movement in a number of axes.
Different types and kinds of the control levers are manufactured, among which US5068499 and US4559420 may be exemplified. In the control levers disclosed in these patent documents, angle sensors must be arranged perpendicular to the control lever and do not allow a direct detection from the control lever, thereby requiring interposition of a second insert. This may cause a reduction in precision. Also, separate sealing measures must be taken for the two sensors used in such structures, and suitable magnetic members must also be utilized corresponding to the present sensors. Additionally, due to the fact that at least two sensor projections will emerge in the control lever, it would be hard to insert it into the device.
In prior art, control levers are used wherein a first axle part is connected to the body and a second axle part is connected on the first axle. An example of such control levers is disclosed in US6462731 (B1 ). In these systems, a magnetic member should exactly face to the integrated circuit (IC) focus, and since the IC must exactly be positioned on the rotation axis and is located at the center, the first axle is formed as a convex and the second axle is formed as a concave so that a space is created therebetween. Further, a main board must be disposed at the lower section, and by the very nature of the system, those parts forming the first and second axles project outward. When it is rotated, an excess space must be created at the lower section, which restricts insertion of a single board close to the center of rotation. It is necessary for the system to retain the arms of the torsion springs utilized at the upper side, and in case said torsion springs are moved to the lower side, the space provided therein must be further increased. Superimposition of the spring arms cannot ensure the feeling that the spring control lever is retained where it is left, thereby complicating production of friction detection systems.
Another control lever of the prior art is ball-joint control lever systems. International patent application no. WO00/39654 may be given as an example for such control levers actuated with ball joints. Also in such systems, the control lever is spherically connected to the body, and it would be hard to eliminate the space which is thus created in the ball joints. Therefore, there is a need to provide a durable control lever with increased precision and increased security.
Finally, document DE 20 2008 008259 U1 discloses a control lever according to the preamble of claim 1.

Objects of the Invention

Principal object of the present invention is to provide a compact, reliable and precise control lever wherein a number of components are eliminated through use of a single printed circuit board.
Another object of the present invention is to provide a control lever with increased security achieved by means of independent springs.
Another object of the present invention is to provide a control lever which prevents an undesired positioning of the spring and maloperation by comprising projections that retain the torsion springs at the center, so that it has an increased security.
Another object of the present invention is to provide a control lever wherein a single magnetic member is sufficient.
Another object of the present invention is to provide a control lever wherein use of single printed circuit board is sufficient.
Another object of the present invention is to provide a control lever which provides a direct connector outlet for the user so that he will not need a cable.
Another object of the present invention is to provide a control lever wherein undesired positioning of the springs and maloperation is prevented by means of projections that retain the torsion springs at the center.
Another object of the present invention is to provide a control lever which prevents unauthorized persons to fill all components of the control lever assembly with resin so as to open the components.
Another object of the present invention is to provide a control lever which ensures effective friction due to the fact that the bottom of the pressure plate is made of TPE material and the upper part thereof is made of a more rigid material.

Summary of the Invention

The present invention relates to a control lever for a heavy equipment, comprising a body; a printed circuit board assembly comprising a printed circuit board having thereon at least one sensor; a lever holder which has a central hole, through which a control arm is at least party engaged, wherein a control arm is rotatable about its longitudinal axis, and which has at least one cocking spring at each end, a magnetic member fastened to an end of said control lever and suitable to interact with the sensor provided on the printed circuit board. The control lever further comprises a C-shaped lever supporting member having an opened section facing to the printed circuit board and arranged to rotate about the longitudinal axis of the lever supporting member; and the control arm is arranged to engage in a slot provided at an upper section of the lever supporting member and at least one cocking spring is provided at each opposite lateral end of the lever supporting member wherein the control arm has a cylindrical connection hole immediately above the magnetic member for attaching the control arm to bushing holes of the lever holder. A bushing is engaged in the cylindrical connection hole and there are bushing connecting members on the right and left sides of the bushing wherein each bushing holes of the lever holder is arranged to receive respective bushing connecting member.

Brief Description of the Figures

The figures of the subject matter control lever, whose brief explanations are herewith provided, are solely intended for providing a better understanding of the present

Figure 2 is a perspective view of the control lever body, a stopper plate and a bellow according to the present invention.
Figure 3 is a perspective view of friction plates used in the control lever according to the present invention.
Figure 4 is a perspective view of the control lever according to the present invention, with printed circuit card and external protection shield.
Figure 5 is a cross-sectional view of the control lever according to the present invention.
Figure 6 is a partial exploded view of the control lever according to the present invention.
Figure 7 is a perspective view of a printed circuit board and housing of the control lever according to the present invention.
Figure 8 is a perspective view showing the connection region of the control lever according to the present invention.
Figure 9 is a partial cross-sectional view showing the connection of the control lever according to the present invention with the protection sheet.
Figure 10 is a perspective view of the printed circuit board of the control lever according to the present invention.
Figure 11a is a longitudinal cross-sectional front view of the control lever according to the present invention.
Figure 11b is a side sectional view of the control lever according to the present invention.
Figure 11c is a longitudinal cross-sectional rear view of the control lever according to the present invention.
Figure 12a is a schematic drawing illustrating the effect of the desired distance between the sensor and the magnetic member due to the control lever according to the present invention.
Figure 12b is a schematic drawing showing the magnetic effect caused by the control lever according to the present invention.

Detailed Description of the Invention

The invention will now be described in detail with reference to the accompanying drawings, wherein reference numerals assigned to the parts therein are listed as follows;

40.: Control lever
1.: Control arm
1a.: Lower portion
1b.: Connection hole
2, 9, 12: Bushing
3.: Bushing connecting element
4.: Lever holder
4a.: Bushing hole
4b.: Central hole
4d.: Pin hole
4e.: Lateral projection
4f.: Montage area
4g.: Spring alignment projection
4j.: Detent recess
6.: Segment
7.: Magnetic member
8.: Pin
9.: Bushing
10.: Cocking spring
10a.: Spring arm
11.: Lever supporting member
11a.: Slot
11c.: Lever supporting projection
11d.: Spring projection
11e.: Inner section
11f.: Alignment projection
11g.: Spring alignment projection
12.: Bushing
13.: Body
13a.: Accommodation space
13b, 13c: Recess
13d.: Spring setting projection
13e.: Rectangular recess
14.: Lower body member
14a.: Lower body cavity
14b, 14c: Cylindrical recess
14d.: Spring alignment projection
15.: Connection area
16.: Stopper plate
16a.: Connecting plate
16c.: Connecting member headspace
16.: Spring space
17.: Connecting bolt
18.: Resin filler
19.: Friction plate
19a.: Friction plate upper section
19c.: Rubber-based material
19b.: Friction plate lower section
19d.: Engagement surface
20.: Pressure spring
21.: Printed circuit board
21a.: Printed circuit board pin
22.: Printed circuit board housing
22a.: Connection hole
22b.: Hole
22c.: Cut hole
22d.: Connector outlet
22e.: Connector inlet
22f.: Resin space
23.: Contact element
24.: Elastic member
25.: Printed circuit board assembly
25a.: Resin filler
26.: Mechanical assembly
27.: Bolt
29.: External protection sheet
30.: Bellow
41.: Detent plate
P: Pivot point
a: Rotation angle

The control lever (40) for a heavy equipment according to the present invention is formed to be used in industrial filed, agriculture, marine vessels, aviation and similar fields of operation. Said control lever (40) mainly comprises at least one body (13), a printed circuit board (21) with a HAil IC (Hall-effect sensor integrated circuit) which is preferably disposed at the center of the body (13) in a horizontal manner, a lever holder (4) fastened to the said body (13) so as to move pivotally about an axis Y, a control arm (1) fastened to the lever holder (4) so as to freely rotate about an axis X, a magnetic member (7) fastened to the lower surface of the control lever and facing to the printed circuit board, and a lever supporting member (11) fastened to the axis X of the control arm (1) such that it can move pivotally. The lever supporting member (11) of the invention is C-shaped, which is arranged such that the closed section of C-shaped structure is located at the upper section, and which has a cavity at the center thereof which is suitable for allowing the control arm (1) to rotate freely at the axis Y, and which comprises at least two cocking springs (10) at each axis.
With reference to figure 1, the control arm (1) is made of a material suitable for being attracted by a magnet, and it has a recess at a lower section (1a) facing to a printed circuit board (21) that is located immediately therebelow, in which recess a suitable magnetic member is received. For the said magnetic member, NdFeB or SmCo may be selected. There is a connection hole (1b) immediately above the recess, and in this cylindrical connection hole, a bushing (2) member corresponding to the hole (1b) is engaged. Disposed at the right and left sides of the bushing (2) member, there is provided one bushing connecting member (3) which is received in a suitable bushing hole (4a) in the lever holder (4).
Again referring to figure 1, there is a hole (4b) at the center of the said lever holder (4), into which said control arm (1) is seated which is then fitted into the bushing holes (4a) by means of a bushing connecting member (3). Furthermore, each bushing (2) member is preferably used together with a suitable segment (6). After the elongated cylindrical rod-shaped control arm (1) is aligned with the opposite bushing holes on the lever holder (4), it is engaged through the bushing (2) and bushing connecting member (3) and into connection hole (1b) and fixed therein by means of a pin that is preferably made of a metal material. As seen in figure 1, rotation of the control arm (1) about the axis X extending along the longitudinal axis of the lever holder is ensured by a central hole (4b) formed in the lever holder.
Referring to figure 1, there is a hollow and preferably circular pin hole (4d) which is provided in the lever holder (4) in order to allow the lever holder (4) to rotate about the axis Y, and which is suitable for receiving a pin (8). After the corresponding pins (8) are engaged into the opposite pin hole (4d), a bushing (9) is inserted onto an outer projection of each pin (8). The spring arms (10a) of a corresponding cocking spring (10) are mounted into the montage area (4f) thereon, with a section of a lateral projection (4e) having a crescent (arc) shape and formed along the longitudinal axis of the lever holder (4) that is substantially formed in a cylindrical form being typically closed, which section facing to the printed circuit board (21). Figure 6 shows a corresponding bushing (9), a cocking spring (10) and the spring arm (10a) mounted on the said control arm (1) as well as the montage area (4f) where they is mounted. Furthermore, figure 6 also includes recesses (13b and 13c) shaped and formed in a suitable manner.
With reference to figure 5, a spring alignment projection (4g) supports the bottom section of the cocking spring (10) where there are no arms, thereby preventing undesired incidents such as undesired displacement of the spring. As seen in figure 1, the lever supporting member (11) having a C-shape has, at the center of its upper section, a slot (11a) which extends transversally. Said control arm (1) is engaged into the slot (11a) so that the control arm (1) is allowed to rotate about the longitudinal axis "Y", as seen in figure 6. At the opposite ends of the lever supporting member (11), there are cylindrical and hollow lever supporting projections (11c), into which bushings (12) are inserted which allow accommodation therein. Preferably two bushings (12) are shaped according to these lever supporting projections (11c) and inserted therein. At the lateral ends of the lever supporting member (11), there are spring projections (11d) formed as a crescent and preferably positioned at that side facing to the printed circuit board (21). Again seen in figure 1, two cocking springs (10) are inserted in the inner surface, i.e. inside (11e), of the opposite spring projections (11d) and set therein. The spring alignment projections (11f) as shown in figure 5 support the bottom side of the spring arm that faces outward so that undesired displacement of the spring is avoided.
With reference to figure 2, there is stopper plate (16) situated under the bellow (30) and a body (13) on which said stopper plate (16) is to be disposed. The control arm (1) is passed through an accommodation space (13a) provided at the center of the said body (13). With reference to figure 6, a plurality of semicircle recesses (13b, 13c) are present on that side of the body (13) facing to the printed circuit board (21), and relevant counter bushings (9, 12) are positioned in these semicircle recesses (13b, 13c). In order words, the spring arms (10a) of the cocking springs (10) are fixed by preferably eight spring setting projections (13d) based on the outer geometry of the said bushings (9, 12). Referring to figure 11a, preferably four connecting members, i.e. nuts are engaged into the said body (13) and they are fitted on the connection areas (15) by means of injection molding. With reference to figure 4, at the center of the cylindrically-shaped lower body member (14) there is a lower body hole (14a), and at its upper side facing to the attachment area, there are cylindrical recesses (14b, 14c), into which counter bushings (9, 12) are positioned. The spring alignment projection (14d) supports the bottom side of the spring where there are no arms and prevents undesired displacement of the spring. The connecting plate (16a) of the stopper plate (16) is inserted into the rectangular recess (13e) situated at the handle side of the said body (13) and is fixed by means of suitable connecting bolts (17) corresponding to the specific connection areas (15). The bolt headspaces (16c) create a volume for resin filler (18) after montage. Loosening of the bolts that due to the vibrations that may occur during use is prevented and an intervention of unauthorized persons to the control lever (40) upon its purchase may be prevented.
Friction surfaces on the upper section of the arc-shaped lateral projections (4e) of the lever holder (4) are sandwiched between the pressure springs (20) of the friction plates (19) and the spring holes (16d) shown in figure 11a. Thus, the user senses friction and the control lever (40) is retained at the position where it is left by the user. As seen in figure 3, each friction plate (19) preferably comprises two pressure springs (20) that extend in vertical direction. At the upper body of the lever holder (4), there are opposite detent recesses (4j), in which the pressure springs (20) of the detent plates (41) are compressed between the spring holes (16d) therein. In this manner, the user is inclined to think that he must exert excess force at the end of the angular movement. This is mostly preferred in applications where the user desires to maintain the last movement. In another preferred embodiment of the invention, such options are available as two free axles, two detent axles, 1 detent axle, 1 free axle (or vice versa), 1 detent axle, 1 friction axle (or vice versa), 1 friction axle 1 free axle (or vice versa), 2 friction axles.
Referring to figure 7, the printed circuit board (21) is fixed to the printed circuit board hole (22) by means of a plurality of screws and through the corresponding connection holes (22a). The inner side of the printed circuit board hole (22) that faces to the control lever has a hole for receiving the printed circuit board (21) also called as PCB. Inside the printed circuit board hole (22), there is a connector outlet (22d) and a connector inlet (22e).
There is a hole (22b) on the lower surface of the printed circuit board hole (22) corresponding to the programming printed circuit board pins (21a) of the printed circuit board, and an elastic member (24) like a seal is interposed between the hole (22b) and the printed circuit board (21). With reference to figure 7, there is a cut hole (22c) on the printed circuit board (21) which enables the EMC contact element (23) to project outward. Figure 7 shows a printed circuit board assembly (25), inside of which is preferably coated with resin filler (25a). With this resin filler, a complete isolation may be achieved during the coating process, except the programming pins. The printed circuit board assembly (25) is fixed to a mechanical assembly (26) shown in figure 10 preferably by means of four bolts (27) which are engaged into the connection areas (15) of the body (13) provided with special nuts. In this way, the entire control lever (40) is established. With reference to figure 8, it is possible to make programming based on the mechanical movement via the opened hole (22b). The programming space is filled with resin filler (25a) so that it is fully sealed, and there is a resin hole (22f) on the area where the bolts are located which may filled with resin filler. In this way, loosening of the bolts due to vibration is prevented and an intervention to the control lever after purchase is avoided.
Referring to figure 9, EMC contact sheet (23) is compressed between the protection sheet and the outer surface of the printed circuit board hole (22), while it is being engaged into the EMC external protection sheet (29), so that it is allowed to have a permanent contact therewith. When the user connects the EMC external protection sheet (29) to a ground line, protection is completed. A bellow (30) which is preferably made of rubber material is placed around the circumference of upper body (13) and a cut seal (31) is fixed on the lower surface of the EMC external protection sheet (29), at its lower side, in order to ensure sealing of the control lever inner chamber.
At either end of the lever holder (4), there are two projections (4e) in the form of a semi spring like an arc, which are opened at that side facing to the printed circuit board (21) and have an arc shape in the direction of the axis Y, and said torsion springs are placed underside of these projections. The lower side (19b) of the friction plates is preferably circular and the surface (4h) of the lever holder seats on the bearing area (11h), at the upper side of which, there is at least one spring. Said spring is pressed against the body (13) or the stopper plate (16) on the body. The lower portion (19b) of the friction plates is made of rubber-based material (19c) and the upper portion (19a) thereof is made of rigid thermoplastic or metal and fixed by means of a clamp-fit surface (19d). Corresponding to those sides of the cocking springs (10) which have no spring arms (10a), there are two projections (4g) on the lever holder (4), and two spring alignment projections (11g) are also present on the movement handle along the axis Y. The printed circuit board assembly (25) is filled with resin filler until the elements of the printed circuit board (21) are located thereunder, and at the lower surface of the printed circuit board hole (22), there is a hole (22b) corresponding to the printed circuit board pins (21a) for programming. There is an elastic member (24) between this hole (22b) and the printed circuit board (21).
The outer surfaces of the corresponding bushing holes (13b, 13c) (14b, 14c) of the upper body (13) and the lower body member (14) are closed, and the upper body (13), the lower body member (14) and the printed circuit board body (22) are made of electrical insulating thermoplastic material. There is an EMC and ESD protection sheet (29) closed at the lower surface, which has a bowl shape and is elevated up to at least one rotation axis, and it is ensured that the EMC protection sheet (29) is in contact with the EMC contact element (23) which is in contact with the printed circuit board (21) and reaches to the outer surface by means of a cut hole (22c) (without an additional connecting element or solder). The ESD sheet protects the control lever (40) against the external effects by means of a grid generated upon a strong magnetic current.
Hall effect sensors have certain criteria for efficient operation. One of them is rotation angle (α), which is determined to be 20° in standard, meaning that it cannot be changed. Another parameter is the distance (h) between the magnetic member and hall-effect sensor, which distance is also determined in standard based on the flux density accepted by the said sensor. It is also not possible to change this parameter in the designing process. Another important distance is the distance (d1, d2) between the rotation point, i.e. pivot point (P) and the magnetic member (7). This is the only parameter that may be mechanically intervened. Reducing the distance between the pivot point (P) and the magnetic member, i.e. the distance d2 as shown in figure 12a increases measurement precision. With the control lever (40) according to the present invention, the gap between the pivot point (P) and the magnetic member (40) may be made shorter compared to that in the single board configuration. Referring to figure 12a, with the invention, the distance (d1) of the pivot point (P) to the magnetic member (7) may be optimized so as to be shorter. Especially upon a full rotation of the magnetic member, and also travelled to the extreme points within the ranges it is allowed to travel, the magnetic angle will not be increased tremendously and the magnetic flux density will be prevented to reduce further so that the hall-effect sensor can make a precise measurement. In figure 12b, it is shown that the distance (d2) between the said pivot point (P) and the magnetic member (7) is kept longer. In this way, if the distance is long, precision will be lower than that in figure 12a.

Claims

A control lever (40) for a heavy equipment, comprising a body (13);
a printed circuit board assembly (25) comprising a printed circuit board (21) having thereon at least one sensor;

a lever holder (4) which has a central hole (4b), through which a control arm (1) is at least party engaged, wherein a control arm (1) is rotatable about its longitudinal axis (Y), and which has at least one cocking spring (10) at each end,

a magnetic member (7) fastened to an end of said control lever (4) and suitable to interact with the sensor provided on the printed circuit board (21),
characterized in that the control lever (40) further comprises:
a C-shaped lever supporting member (11) having an opened section facing to the printed circuit board (21) and arranged to rotate about the longitudinal axis (X) of the lever supporting member (11); and

the control arm (1) is arranged to engage in a slot (11a) provided at an upper section of the lever supporting member (11) and at least one cocking spring (10) is provided at each opposite lateral end of the lever supporting member (11) wherein the control arm (1) has a cylindrical connection hole (1b) immediately above the magnetic member (7) for attaching the control arm (1) to bushing holes (4a) of the lever holder (4) and in that a bushing (2) is engaged in the cylindrical connection hole (1b) and there are bushing connecting members (3) on the right and left sides of the bushing (2) wherein each bushing holes (4a) of the lever holder (4) is arranged to receive respective bushing connecting member (3).
A control lever (40) according to claim 1, characterized by comprising a C-shaped lateral projection (4e) at the opposite ends of the said lever holder (4), against which the cocking spring (10) abut, and which is formed such that its opened section faces to the electronic circuit board.
A control lever (40) according to claim 1, characterized by comprising a C-shaped spring projection (11d) at the opposite ends of the said lever supporting member (11), against which the cocking spring (10) will abut, and which is formed such that its opened section faces to the electronic circuit board.
A control lever (40) according to claim 1, characterized by comprising a plurality of friction plates (19) which are placed on the lever holder (4).
A control lever (40) according to claim 4, characterized in that the lower section (19b) of each friction plate is formed as a concave and comprises at least one pressure spring (20) which interacts with a stopper plate.
A control lever (40) according to claim 4 or 5, characterized in that the lower section (19b) of the said friction plate is made of rubber-based material and the upper section (19a) of the friction plate is made of rigid thermoplastic or metal.
A control lever (40) according to claim 1, characterized by comprising at least one spring alignment projection (4g) on the lever holder (4) and at least one spring alignment projection (11g) on the lever supporting member (11) corresponding to the opposite side of the spring arm (10a) of the said cocking springs (10).
A control lever (40) according to claim 1, characterized in that said printed circuit board assembly (25) comprises a resin filler (18) coated therein so as to ensure its sealing.
A control lever (40) according to claim 8, characterized in that the printed circuit board housing (22) comprises a hole (22b) corresponding to the printed circuit board pin (21a) and an elastic member (24) interposed between the hole (22b) and the printed circuit board (21).
A control lever (40) according to claim 1, characterized by comprising a plurality of semicircle recesses (13b, 13c) on that side of the body (13) facing to the printed circuit board (21), and relevant counter bushings (9, 12) positioned in these semicircle recesses (13b, 13c).
A control lever (40) according to claim 1, characterized in that said upper body (13), the lower body member (14) and the printed circuit board housing (22) are made of electrical insulating thermoplastic material.
A control lever (40) according to claim 1, characterized by comprising at least one external protection sheet (29).
A control lever (40) according to claim 12, characterized by comprising a contact element (23) which is in contact with the printed circuit board (21) and reaches to the outer surface by means of a cut hole (22c) is in contact with the external protection sheet (29) such that they interact with each other.
A control lever (40) according to claim 1, characterized by comprising a stopper plate (16) and at least one connecting element headspace (16c) on the stopper plate (16) which is suitable to be filled with resin material.
A control lever (40) according to any one of the preceding claims, characterized in that said sensor is a Hall-effect sensor.