阅读说明：本技术 带锁定指示器的可锁定线性致动器 (Lockable linear actuator with locking indicator ) 是由 C·佩特纳兹 L·蒙萨因 于 2019-08-06 设计创作，主要内容包括：本发明涉及一种伸缩式致动器,包括气缸(2),杆(3)安装在气缸(2)中以沿着滑动轴线(X)滑动,该致动器包括：锁定构件,该锁定构件包括锁定指状件(10),该锁定指状件(10)沿着垂直于滑动轴线的锁定方向(Y)在锁定位置和缩回位置之间可移动,在该锁定位置,锁定指状件(10)的端部(9)接合在杆的凹槽(8)中,以便将杆锁定在适当位置,在该缩回位置,指状件的端部从凹槽脱离,以便释放杆；锁定指示器(20),该锁定指示器(20)固定到锁定指状件,以在当锁定指状件处于锁定位置时指示锁定的位置和当锁定指状件处于缩回位置时指示解锁的位置之间可移动,该致动器的特征在于,锁定指示器通过连接部(22、23、24)固定到锁定指状件,该连接部(22、23、24)在指状件的端部断裂、同时杆被锁定的情形下适于被中断,推力弹簧(25)布置在锁定指状件中以在所述连接部中断时朝向指示解锁的位置推压锁定指示器。(The invention relates to a telescopic actuator comprising a cylinder (2), a rod (3) being mounted in the cylinder (2) so as to slide along a sliding axis (X), the actuator comprising: a locking member comprising a locking finger (10), the locking finger (10) being movable along a locking direction (Y) perpendicular to the sliding axis between a locking position, in which an end (9) of the locking finger (10) engages in the groove (8) of the lever so as to lock the lever in position, and a retracted position, in which the end of the finger disengages from the groove so as to release the lever; a lock indicator (20), the lock indicator (20) being fixed to the locking fingers to be movable between a position indicating locked when the locking fingers are in the locked position and a position indicating unlocked when the locking fingers are in the retracted position, the actuator being characterized in that the lock indicator is fixed to the locking fingers by means of a connection (22, 23, 24), the connection (22, 23, 24) being adapted to be interrupted in case the ends of the fingers break while the rod is locked, a thrust spring (25) being arranged in the locking fingers to urge the lock indicator towards the position indicating unlocked when said connection is interrupted.)

1. Telescopic actuator comprising a cylinder (2), a rod (3) being mounted in said cylinder (2) so as to slide along a sliding axis (X), said actuator comprising: a locking member comprising a locking finger (10), said locking finger (10) being movable along a locking direction (Y) perpendicular to said sliding axis between a locking position, in which an end (9) of said locking finger (10) engages in a groove (8) in said lever so as to lock said lever in position, and a retracted position, in which said end of said finger disengages from said groove so as to release said lever; a locking indicator (20), said locking indicator (20) being fixed to said locking finger so as to be movable between a position indicating locking when said locking finger is in said locked position and a position indicating unlocking when said locking finger is in said retracted position, said actuator being characterized in that said locking indicator is fixed to said locking finger by means of a connection (22, 23, 24), said connection (22, 23, 24) being adapted to be interrupted in case said end of said finger breaks while said rod is locked, a thrust spring (25) being arranged in said locking finger to urge said locking indicator towards said position indicating unlocking when said connection is interrupted, while said locking finger remains in said locked position.

2. Actuator according to claim 1, wherein the locking indicator is engaged in a hole (21) of the locking finger (9) and is fixed to a frangible support (22), the frangible support (22) ending with a foot (23) connected to the end of the locking finger by a retaining ring (24).

3. Actuator according to claim 1, characterized in that a detector (32) is provided for generating a signal taking two values depending on whether a target (31) connected to the locking indicator is close to or remote from the detector.

4. Actuator according to claim 3, wherein the target is carried by a crank (30), the crank (30) being hinged to the cylinder of the actuator and connected to the locking indicator.

Technical Field

The invention relates to a telescopic lockable actuator with a locking indicator.

Background

Telescopic actuators are known, for example hydraulic actuators, which comprise a cylinder in which a rod is mounted to slide along a sliding axis, and which comprise a locking member to automatically lock the rod to the cylinder when the rod reaches one of its extreme positions.

There are various types of locking members, including locks that utilize claws, segments, or indeed fingers. When the finger is used, it is mounted on a cylinder to move along a locking axis perpendicular to the sliding axis between a locking position, in which it is urged towards the locking position by a spring so as to penetrate into a groove in the rod, and a retracted position, in which it is urged against the spring by fluid under pressure admitted into a chamber of the actuator into which the finger penetrates. The sleeve is mounted on the cylinder for movement along the sliding axis between a retracted position into which the sleeve is urged by the lever as the lever approaches the locking position and a position for holding the fingers in the retracted position into which the sleeve is urged by the spring for movement under pressure under the fingers that are retracted by the fluid.

It is known to equip the fingers with indicators or some other detector means to indicate the position where the fingers are to be found and thus to indicate whether the lever is locked or unlocked. However, when the lever is locked, it may happen that the actuator lever is subjected to a force that causes the ends of the fingers to break. The lever will appear locked even if the broken fingers are unable to hold the lever in place.

Disclosure of Invention

The present invention seeks to provide a linear actuator which is lockable by means of fingers and in which the indicator member serves to detect non-locking even if the fingers appear to be in a locked position.

To achieve this object, there is provided a telescopic actuator including a cylinder in which a rod is mounted to slide along a sliding axis, the actuator including: a locking member including a locking finger movable in a locking direction perpendicular to the sliding axis between a locking position in which an end of the locking finger engages in the groove in the lever to lock the lever in position and a retracted position in which the end of the finger disengages from the groove to release the lever; a lock indicator secured to the lock finger to be movable between a position indicating locking when the lock finger is in the locked position and a position indicating unlocking when the lock finger is in the retracted position. According to the invention, the locking indicator is fixed to the locking fingers by means of a connection adapted to be interrupted in the event of breakage of the ends of the fingers while the lever is locked, a thrust spring being arranged in the locking fingers to urge the locking indicator towards a position indicating unlocking when said connection is interrupted.

Thus, even if the finger is broken, the locking indicator provides reliable information by assuming its position indicating unlocked even when the end of the finger has been broken and the locking finger remains in its locked position.

In a preferred embodiment of the invention, the indicator is associated with a frangible support that extends in the aperture of the locking finger so as to be connected to an end thereof. Thus, the breaking end causes the frangible support to break, thereby disengaging the locking indicator, which can then be moved by the thrust spring.

Drawings

The invention may be better understood in light of the following description of specific embodiments of the invention with reference to the figures of the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of a lockable telescopic actuator in a specific embodiment of the invention, the stem of the actuator being shown in the locked position, the locking fingers being shown in the locked position, and the indicator being shown in its position indicating locking;

FIG. 2 is a view similar to the view of FIG. 1, with the lever in the process of being unlocked, the finger pushed into the retracted position, and the indicator in its position indicating unlocking;

FIG. 3 is a view similar to the view of FIG. 2, with the lever unlocked and the finger blocked in the retracted position, with the indicator in its position indicating unlocked;

FIG. 4 is a view similar to the view of FIG. 1, with the fingers in the locked position, but with the ends of the locking fingers broken by the lever, and the indicator pushed into its position indicating unlocked;

FIG. 5 is a detailed view, on a larger scale, of the connection between the locking indicator and the locking finger; and

fig. 6 to 9 are drawings similar to fig. 1 to 4, showing a variant embodiment of the invention.

Detailed Description

With reference to fig. 1 to 4, the invention applies to a telescopic actuator, in particular in this example to a hydraulic actuator 1, comprising a hollow cylinder 2, in which a rod 3 associated with a piston 4 is mounted to slide in a sealed manner along a sliding axis X inside the cylinder 1 so as to define an uninterrupted (or "piston") chamber 5 extending between the piston 4 and an uninterrupted end wall (not shown) of the cylinder, and an annular chamber 6 extending between the piston 4 and a perforated (i.e., "interrupted") end wall 7 through which the rod 3 protrudes 7.

The piston 4 comprises a groove 8 for receiving an end 9 of a locking finger 10, the locking finger 10 being mounted to slide in a sealed manner in a housing 11 of the cylinder 1 along a locking axis Y perpendicular to the sliding axis X between a locking position, as shown in fig. 1, in which the end 9 is engaged in the groove 8 so as to block the rod 3 in the extended position, and a retracted position, as shown in fig. 2 and 3, in which the end 9 is disengaged from the groove 8 so as to release the rod 3.

The locking fingers 10 are pushed towards the locking position by the locking spring 12, which locking spring 12 abuts against the plug 13 closing the housing 11. When fluid under pressure is admitted into the annular chamber 6, the locking fingers 10 are pushed into the retracted position. The sleeve 14 is arranged in the cylinder 1 to slide along the sliding axis X between a retracted position, shown in fig. 1, towards which the sleeve 14 is pushed by the piston 4 against the return spring 15 when the rod 3 is in the locking position, and a blocking position, shown in fig. 3, into which the sleeve 14 is pushed by the return spring 15 when the locking finger 10 is in the retracted position, in order to retain it there and block it in this position even if the annular chamber 6 is no longer under pressure.

As shown in fig. 1, the locking fingers 10 are associated with a locking indicator 20, the locking indicator 20 projecting from the plug 13 so as to be visible from the outside. The locking indicator 20 is fixed to a rod 26, the rod 26 engaging in a central hole 21 in the locking finger 10. As can be seen more particularly in fig. 5, the stem 26 extends through a frangible support 22 of smaller section terminating in a foot 23, which foot 23 is fixed to the locking finger 10 at the end 9 of the locking finger 10 by a retaining ring 24. A thrust spring 25 extends around the rod 26 in a housing 27 of the locking finger 10, abutting against an end wall of the housing 27 and against a shoulder of the indicator 10, so as to urge the indicator 20 outwards. In the case shown, the retaining ring 24 holds the locking indicator 20 against the thrust spring 25.

The operation of the assembly is described below. In the situation shown in fig. 1, the end 9 of the locking finger 10 engages in the groove 8 of the piston 4, thereby locking the rod 3 in position (in particular in the extended position). The locking spring 12 holds the locking finger in the locked position. The lock indicator 20 is in its position indicating locking.

Admitting fluid under pressure into the annular chamber 6 moves the locking fingers 10 towards their retracted position, as shown in figure 2, thereby releasing the lever 3. The lock indicator 20 is in its position indicating unlocked.

Released in this way, the rod 3 can move in the cylinder 2, having the effect of moving the sleeve 14 towards the blocking position, driven from the return spring 15, so as to keep the locking finger 10 in the retracted position, as shown in fig. 3. The locking indicator 20 is thus held in its position indicating unlocking.

Thereafter, when fluid is admitted under pressure into the uninterrupted chamber 5, the rod 3 returns towards its extended position until it pushes the sleeve 14 back against the spring 15, so that the end 9 of the locking finger 10 can penetrate into the groove 8 under the action of the locking spring 12 in order to lock the rod 3. The lock indicator 20 returns to its position indicating locking.

In some cases, a load coupled to the lever may exert a large force on the lever 3 while the lever 3 is in the locked position. In some special cases the force is so great that it causes the locking fingers 10 to break by breaking apart the ends 9 of the locking fingers 10. The lever 3 is thus released even if the locking finger 10 remains in the locked position, as shown in fig. 4.

However, breaking the end 9 of the locking finger 10 causes the frangible support 21 to break simultaneously, thereby breaking the connection between the locking indicator 20 and the locking finger 10. The locking indicator 20 is thus released and pushed by the thrust spring 25 towards its position indicating unlocking, even if the locking finger 10 remains in the locked position. This arrangement serves as an indication to avoid the locking indicator providing locking when in practice the lever 3 is actually released.

Instead of a visual indication, it may be advantageous to detect the position of the locking indicator by means of a detector adapted to generate an electrical signal taking two distinct values. In a variant of the invention shown in fig. 6 to 9, in which the common elements are given the same reference numbers as in fig. 1 to 4, the locking indicator 20 is used to actuate a crank 30 carrying a target 31 facing the detector 32 and which is moved between a position close to the detector 32, corresponding to the position indicating locking, as shown in fig. 6, and a position far from the detector 32, corresponding to the position indicating unlocking, as shown in fig. 7 to 9, so that the detector 32 generates an electrical signal taking two distinct values, enabling it to distinguish between the two indicated positions. In this example, the crank 30 is hinged to a pivot 33, the pivot 33 being fixed to the plug 13 and extending through an elliptical opening 34 in the crank 30. The crank 30 is also hinged to a collar 35, the collar 35 being clamped directly onto the outer end of the lock indicator 20. Thus, movement of the locking indicator 20 causes the crank 30 to pivot, thereby moving the target 31 between its two positions respectively closer to and further from the detector 32.

The invention is not limited to the above description but, on the contrary, covers any modifications coming within the scope defined by the claims.