Abstract: A first piston (4) which is coupled to an output rod (2) and which is inserted in a housing (3) is driven upward by a pressurized fluid. A second piston (6) which is arranged above the first piston (4) is driven downward. This causes a wedge-type force multiplier (M), arranged above the first piston (4), to carry out force multiplication driving with respect to the output rod (2).

Abstract: A first piston (21) is coupled to an output rod (2) inserted in a housing (1). A second piston (22) is inserted in the housing (1) radially outside of the output rod (2). A force multiplier (36) has a wedge space (39) and a plurality of engaging balls (40). When force multiplication driving is started, the wedge space (39) is formed between a transmitting portion (37) provided in the output rod (2) and a receiving portion (38) provided in the housing (1) so as to get narrower as it extends radially inward. Before the force multiplication driving is started, the engaging balls (40) are brought into contact with an outer circumferential surface of the output rod (2), and when the force multiplication driving is started, the engaging balls (40) are pushed out toward the wedge space (39) to engage with the transmitting portion (37).

Abstract: An output rod (27) is inserted in a housing (4) so as to be movable vertically. A first piston (41) inserted in a lower part of the housing (4) is fixed to the output rod (27). A second piston (42) inserted on an upper side of the first piston (41) is fitted on the output rod (27) so as to be movable vertically. A lock chamber (44) is provided between the first piston (41) and the second piston (42). A first release chamber (51) is provided below the first piston (41). A second release chamber (52) is provided above the second piston (42). During force multiplication driving of the output rod (27), a pressurized fluid in the lock chamber (44) carries out the force multiplication driving with respect to the output rod (27) downward via the second piston (42) and engaging balls (69). A retaining spring (60) which biases the second piston (42) upward is provided in the lock chamber (44) between the first piston (41) and the second piston (42).

Abstract: An annular piston is vertically movable and rotatable. A guide groove is provided in an outer peripheral portion of the annular piston, and an engaging ball to be fitted into the guide groove is provided on an inner peripheral wall of a cylinder hole. A transmission mechanism prevents the clamp rod and the annular piston from rotating relatively to each other and permits them to move relatively to each other in a vertical direction. When the clamp rod is moved from a released raised position to a locked lowered position, the annular piston descends while rotating via a rotational groove and the engaging ball, and the annular piston causes the clamp rod to rotate, causing the clamp rod to descend straight down.

Abstract: A first piston for high load is inserted into a housing so as to be movable vertically, and a second piston for low load is inserted into a cylindrical hole of the first piston so as to be movable vertically. An output portion projects from the second piston to above the housing. A first spring for high load and a second spring for low load are mounted in a spring chamber defined by both pistons and. Both springs and are mounted so as to urge the first piston and the second piston upward. A switching mechanism disposed in the pressure fluid chamber at a side opposite to the spring chamber, connects the first piston selectively to the housing or the second piston.

Abstract: A first piston (10) is inserted in a housing (2) so as to be hermetically movable vertically. A second piston (20) is inserted in a cylindrical hole (14) of the first piston (10) so as to be hermetically movable axially, and has an output rod (26) projecting upward from the housing (2). A lock chamber (40) is formed below the first piston (10) and the second piston (20), and a release chamber (42) is formed above the first piston (10) and the second piston (20). A force multiplier (52) is arranged in the housing (2) so as to cause (i) a first force, with which a pressurized fluid supplied into the lock chamber (40) pushes the first piston (10) upward, to be transformed in a force-multiplying manner into a second force and (ii) the second force to be transmitted to the second piston (20). Further, a change-over mechanism (54) is arranged in the housing (2) so as to selectively couple the first piston (10) to the housing (2) or the second piston (20).

Abstract: An output rod (2) is inserted in a housing (1) so as to be movable vertically. A first piston (21) inserted in an upper part of the housing (1) is fixed to the output rod (2), and a second piston (22) inserted in a lower part of the housing (1) is fitted on the output rod (2) so as to be movable vertically. A lock chamber (25) is arranged between the first piston (21) and the second piston (22), and a first release chamber (31) and a second release chamber (32) are arranged above the first piston (21) and below the second piston (22), respectively. Supply of a pressurized fluid into the lock chamber (25) in lock driving of the output rod (2) first causes the first piston (21) to be driven upward to drive the output rod (2) upward, and then causes the second piston (22) to be driven downward to drive the output rod (2) upward in a force-multiplying manner via a force multiplier (36).

Abstract: An annular piston is vertically movable and rotatable. A guide groove is provided in an outer peripheral portion of the annular piston, and an engaging ball to be fitted into the guide groove is provided on an inner peripheral wall of a cylinder hole. A transmission mechanism prevents the clamp rod and the annular piston from rotating relatively to each other and permits them to move relatively to each other in a vertical direction. When the clamp rod is moved from a released raised position to a locked lowered position, the annular piston descends while rotating via a rotational groove and the engaging ball, and the annular piston causes the clamp rod to rotate, causing the clamp rod to descend straight down.

Abstract: A clamp rod (5) is vertically movably inserted into a housing (3), and a detection hole (58) is formed in a lower end wall (3b) of the housing (3), substantially concentrically with an axis of the clamp rod (5). An inlet hole (71, 72) for supplying compressed air is opened in a peripheral surface of the detection hole (58). Into the detection hole (58), a detection member (62) is fitted vertically movably, the detection member (62) having a closing surface (68) which closes an opening portion (71a, 72a) of the inlet hole (71, 72), and a recessed portion (69) through which the opening portion (71a, 72a) is communicatively connected to outside air. The detection member (62) is connected to a downward projecting portion (5a) of the clamp rod (5). The detection member (62) is urged by an elastic member (91) toward the opening portion (71a, 72a).

Abstract: A clamp rod (5) is vertically movably inserted into a housing (3), and a detection hole (58) is formed in a lower end wall (3b) of the housing (3), substantially concentrically with an axis of the clamp rod (5). An inlet hole (71, 72) for supplying compressed air is opened in a peripheral surface of the detection hole (58). Into the detection hole (58), a detection member (62) is fitted vertically movably, the detection member (62) having a closing surface (68) which closes an opening portion (71a, 72a) of the inlet hole (71, 72), and a recessed portion (69) through which the opening portion (71a, 72a) is communicatively connected to outside air. The detection member (62) is connected to a downward projecting portion (5a) of the clamp rod (5). The detection member (62) is urged by an elastic member (91) toward the opening portion (71a, 72a).

Abstract: A piston (19) inserted into a cylindrical housing (2) is connected to a clamp rod (5). A lock chamber (20) is provided above the piston (19), and an annular valve chamber (41) is formed in a peripheral wall of a rod hole (18) into which the clamp rod (5) is inserted. At a last stage of swing ascending of the clamp rod (5), a shuttle member (42) fitted at the outside of a lower portion of the clamp rod (5) ascends and fits into the valve chamber (41) due to a differential pressure of a pressurized oil applied when the shuttle member (42) starts to fit into the valve chamber (41). Then, a flow rate of the pressurized oil to be discharged from the lock chamber (20) is controlled by a restriction gap between the shuttle member (42) and the clamp rod (5). At an early stage of swing descending of the clamp rod (5), a flow rate of the pressurized oil to be supplied to the lock chamber (20) is controlled by a restriction gap between the valve chamber (41) and the shuttle member (42).

Abstract: A housing (3) has an upper end wall (3a) which supports an upper slide portion (11) of a clamp rod (5) vertically movably. The housing (3) has a lower end wall (3b), a support cylinder (13) of which supports a lower slide portion (12) of the rod (5) vertically movably. The rod (5) is provided with an input portion (14) between the upper slide portion (11) and the lower slide portion (12). A clamp spring (20) connected to the input portion (14) drives the rod (5) downwards for clamping. The lower slide portion (12) has an outer periphery provided with a helical rotary groove (27) and a straight groove (28) which is in upward continuity with the rotary groove (27). A ball (29) engages with the rotary groove (27) and the straight groove (28). The ball (29) is supported by an inner wall (13a) of the support cylinder (13).

Abstract: A multi-display video display system includes a plurality of display units and video signal processing units respectively associated with the display units, and displays a single image by using the video signal processing units. The video signal processing units receive a video signal of the same original image, divide the video signal so as to be associated with the display units, and generate a division display signal, receive the video signal of the same original image, acquire an average luminance level based on the video signal preceding the division and average luminance levels respectively for video signals obtained by the division, select one from among the acquired average luminance levels, and supply it to the display units, respectively. The display units control display brightness on the basis of the average luminance level supplied from the video signal processing units, respectively.

Abstract: A clamp rod (5) is vertically movably inserted into a housing (3). The housing (3) has a lower end wall (3b) formed with a detecting hole (58) substantially concentrically with an axis of the clamp rod (5). The detecting hole (58) has a peripheral surface opened to provide at least one inlet hole (71, 72) for supplying compressed air. A detecting member (62) is vertically movably fitted into the detecting hole (58). The detecting member (62) has an outer peripheral surface provided with a closing surface (68) which closes an opening portion (71a, 72a) of the inlet hole (71, 72) and with a recess (69) which communicates the opening portion (71a, 72a) with the outside air. The clamp rod (5) has a downwardly oriented projection (5a). The projection (5a) is connected to the detecting member (62) so that it can make a relative movement radially.

Abstract: A housing (3) has an upper end wall (3a) and a lower end wall (3b) which support an upper slide portion (11) and a lower slide portion (12) of a clamp rod (5) vertically movably, respectively. The rod (5) is moved downwards for clamping through a clamp spring (20). The lower slide portion (12) has an outer periphery provided with guide grooves (26), each of which comprises a helical rotary groove (27) and a straight groove (28), peripherally in plural number. Engaging balls (29) which are fitted into the respective guide grooves (26) are rotatably supported by through holes (31) provided in an upper portion of the lower end wall (3b). A sleeve (35) is externally fitted over the engaging balls (29) rotatably around an axis.

Abstract: A clamp rod (5) is inserted into a housing (3) rotatably around an axis and movably downwards for clamping. The clamp rod (5) has an outer peripheral portion formed with three guide grooves (26) which are arranged peripherally at substantially the same spacing. An engaging ball (29) which is fitted into every guide groove (26) is supported by a lower end wall (3b) of the housing (3). Each of the guide grooves (26) comprises a rotary groove (27) and a straight groove (28) which is in upward continuity with the rotary groove (27). The rotary grooves (27) as well as the straight grooves (28) are arranged in parallel with one another. A partition wall between the adjacent guide grooves (26), (26) has a minimum thickness (T) set to a value smaller than a diameter (D) of the engaging ball (29).

Abstract: A housing (3) has an upper end wall (3a) and a lower end wall (3b) which support an upper slide portion (11) and a lower slide portion (12) of a clamp rod (5) vertically movably, respectively. The rod (5) is moved downwards for clamping through a clamp spring (20). The lower slide portion (12) has an outer periphery provided with guide grooves (26), each of which comprises a helical rotary groove (27) and a straight groove (28), peripherally in plural number. Engaging balls (29) which are fitted into the respective guide grooves (26) are rotatably supported by through holes (31) provided in an upper portion of the lower end wall (3b). A sleeve (35) is externally fitted over the engaging balls (29) rotatably around an axis.

Abstract: A clamp rod (5) is vertically movably inserted into a housing (3). The housing (3) has a lower end wall (3b) formed with a detecting hole (58) substantially concentrically with an axis of the clamp rod (5). The detecting hole (58) has a peripheral surface opened to provide at least one inlet hole (71, 72) for supplying compressed air. A detecting member (62) is vertically movably fitted into the detecting hole (58). The detecting member (62) has an outer peripheral surface provided with a closing surface (68) which closes an opening portion (71a, 72a) of the inlet hole (71, 72) and with a recess (69) which communicates the opening portion (71a, 72a) with the outside air. The clamp rod (5) has a downwardly oriented projection (5a). The projection (5a) is connected to the detecting member (62) so that it can make a relative movement radially.

Abstract: A clamp rod (5) is inserted into a housing (3) rotatably around an axis and movably downwards for clamping. The clamp rod (5) has an outer peripheral portion formed with three guide grooves (26) which are arranged peripherally at substantially the same spacing. An engaging ball (29) which is fitted into every guide groove (26) is supported by a lower end wall (3b) of the housing (3). Each of the guide grooves (26) comprises a rotary groove (27) and a straight groove (28) which is in upward continuity with the rotary groove (27). The rotary grooves (27) as well as the straight grooves (28) are arranged in parallel with one another. A partition wall between the adjacent guide grooves (26), (26) has a minimum thickness (T) set to a value smaller than a diameter (D) of the engaging ball (29).

Abstract: A housing (3) has an upper end wall (3a) which supports an upper slide portion (11) of a clamp rod (5) vertically movably. The housing (3) has a lower end wall (3b), a support cylinder (13) of which supports a lower slide portion (12) of the rod (5) vertically movably. The rod (5) is provided with an input portion (14) between the upper slide portion (11) and the lower slide portion (12). A clamp spring (20) connected to the input portion (14) drives the rod (5) downwards for clamping. The lower slide portion (12) has an outer periphery provided with a helical rotary groove (27) and a straight groove (28) which is in upward continuity with the rotary groove (27). A ball (29) engages with the rotary groove (27) and the straight groove (28). The ball (29) is supported by an inner wall (13a) of the support cylinder (13).